How to catch a train from the sky

What if trains could scale up and down the exterior of huge skyscrapers to create vertical rail stations?

The proposal by UK-based designers Christopher Christophi and Lucas Mazarrasa calls for tall cylindrical skyscrapers to replace the existing flagship train stations that have a large footprint.

Thanks to the towers' small footprint, the remaining land could be turned into large urban parks, say the architects.

The vertical stations are envisioned as repeatable structured that could be built in any city around the world. "Each tower is designed to connect to a new Hyper Speed under and over ground rail network, with trains covering an average distance of 300 miles in 30 minutes," say the designers.

"Therefore, this would not only save time to users and simplify the way we use public transport, but will also help to reduce CO2 emissions by replacing other ways of transport powered by fossil fuels," they add.

That would free up lots of space in tomorrow's megacities, say the two architects behind the futuristic concept of the Vertical Hyper-Speed Train Hub

The two architects say that by 2075 cities will be challenged by significant overcrowding and a shrinkage of publicly-available land.

• A futuristic proposal flips the traditional designs of today's major train stations vertically


• The Vertical Hyper-Speed Train Hub wants to cut the footprint of rail terminals by 2075


• The proposal won an Honorable Mention in 2014's eVolo Skyscraper competition

On The Move explores the world of future personal transport looking at the latest trends and tech innovations that shape global travel.

(CNN) -- For decades, skyscrapers have served as iconic symbols of national pride or flashy trophies of corporate wealth, reshaping the skyline of the world's major urban centers. Perhaps in the future, the high-rise superstructures could also help revolutionize the way we travel.

That, at least, is the fanciful concept behind the Vertical Hyper-Speed Train Hub, a futuristic proposal of two UK-based architects envisaging trains roaring up and down the side of specially-designed skyscrapers nearly as high as the Empire State Building.

Towering above the crowded streets of future metropolises, these giant buildings are designed to minimize the large slices of real estate that major railway terminals occupy by flipping them on their side.

Vertical train stations in London by 2075?

Courtesy Christopher Christophi and Lucas Mazarrasa

The goal, designers Christopher Christophi and Lucas Mazarrasa say, is to free up valuable space in the densely-packed cities of tomorrow, which will be significantly challenged by overcrowding and a sharp drop in public space availability.

"In 60 years' time, it will be very difficult for governments to find attractive pieces of available land for public use in the heart of megacities," says Christophi, 27. "Governments will be able to take advantage of such spaces in order to re-adapt the cities' structure to society needs," he adds.

How it works

The designer's vertical station concept calls for a tall cylindrical skyscraper whose small footprint would allow the transformation of the surrounding area into an urban park. Passengers arriving at the tower would use a lift to make their way up into the platform and from there into their carriage, which could accommodate 10 people sat in two rows opposite each other.

The atrium will be the main circulation space for commuters coming to the tower.

Courtesy Christopher Christophi and Lucas Mazarrasa

But, you might wonder by now, how could commuters stay on their feet whilst the train slides in hyper speeds along the huge tower's façade?

The main idea is that instead of traveling on normal rails beneath, the carriages would be supported by magnetic tracks running up the skyscraper's exterior. Each carriage proportion is designed as a cubical shape to enable it to function both vertically, when docked, and horizontally, while traveling After the train's departure, the wagons would pivot like a "Ferris wheel," allowing commuters to remain in an upright position and enjoy breathtaking views of the city.

Connecting cities

The radical proposal won the designers an Honorable Mention at this year's eVolo Skyscraper competition, which encouraged people from around the world to propose new ideas for vertical structures of the future.

The designers say the towers, which would be capped off by a rooftop green plaza, are envisioned as individual pieces of infrastructure that could be replicated in cities around the world.

Our conceptual design is based upon utilizing existing and viable technologies that can currently be seen in hyper speed rail networks.

Lucas Mazarrasa, architect

The hope is to connect a new hyper-speed network of underground tunnels and overground routes where superfast trains would cover distances of 300 miles in 30 minutes. This, they claim, would not only save commuting time and simplify the way public transport is being used, but would also help to cut down CO2 emissions by replacing ways of transport powered by fossil fuels.

"Our conceptual design is based upon utilizing existing and viable technologies that can currently be seen in hyper speed rail networks, for example in China," says Mazarrasa, 29, adding that is a matter of time before we're able to reach the rail speeds their concept requires.

"The Maglev trains currently travel at 360 miles per hour -- this technology by the 2075 will in no doubt move leaps and bounds from what it already is today, making the hyper-speed trains probably the fastest and safest way of transporting goods and people."

Of course, there are a number of limitations to the project -- the proposal deals only with stations designed to accommodate city by city travel, not to mention efficiency issues around loading trains in high volume terminals and connecting train routes.

Yet, like in most futuristic transport proposals, practical details are best to take a back seat for now to allow us to enjoy the thrilling ride -- that is, unless you're afraid of heights.

Boehner: Don't repeat Iraq mistakes

A U.S. soldier patrols outside FOB Shank In Afghanistan.

• House Speaker John Boehner says the U.S. needs to finish the job right in Afghanistan


• The progress, he says, has been significant, but the country will continue to have setbacks


• He argues that there is a shared, bipartisan legacy in Washington for Afghanistan


• Boehner: History will judge us not on whether we ended wars, but how we ended them

Editor's note: Rep. John Boehner (R-Ohio) has been Speaker of the House since 2011. You can follow him on Twitter @SpeakerBoehner. The opinions expressed in this commentary are solely those of the author.

(CNN) -- Three weeks ago, I had the privilege of visiting our civilian leaders and military commanders, as well as our troops, in Afghanistan. It was my fourth trip to the country and a vastly different one than my first visit in 2007.

Flying over Kabul at night, I was struck by the changes: Electric lights and even traffic are visible throughout the valley. I was encouraged by what I saw and by what I heard from Ambassador James Cunningham and General Joseph F. Dunford, Jr.

The Afghans are taking the lead for their own security, and now they are poised to successfully transition to a new government for the first time in their history.

After 13 years, I am often asked why Afghanistan still matters. The world is growing more complicated by the day, and, in my view, more dangerous. The responsibility is on leaders in Washington to remind the American people why finishing the job right in Afghanistan remains important.

The explanation is straightforward: Not only was it the location from which the 9/11 attack that killed 3,000 Americans was planned, but the country also remains uniquely vulnerable to becoming a terrorist stronghold again if we don't complete our work to empower the Afghan people, security forces and government to protect their own country.

Our mission quite simply is to prevent another terrorist attack.

And, there's another reason we don't talk about much, but it remains equally important. Both friends and foes are watching to see whether America has the resolve to complete its task or if we will fall short of our mark out of fatigue or political expediency. This has ramifications not just for Afghanistan but other critical areas where America has strategic national security interests.

Make no mistake, Afghanistan remains a tough fight. The progress has been significant, but the country will continue to have setbacks. Violence, like the recent tragic shooting at a Kabul hospital, is going to continue. Terrorist organizations will continue to attempt high-profile attacks to break our resolve.

But because of the courage and sacrifices of our deployed men and women, both military and civilian, I am optimistic that we can achieve our mission successfully if Washington doesn't squander this progress.

At the time of my visit, I said that I hoped Washington and Kabul would always be worthy of the shared sacrifice and effort that our troops, the international community, and the Afghan people have made. The biggest takeaway from my visit is that of all the challenges facing our strategy for Afghanistan, the most potentially damaging and completely avoidable is quitting just short of the goal line.

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It's essential that we do not repeat the same mistakes in Afghanistan that we made in Iraq. Before the end of this year, the Obama administration must reach a bilateral security agreement with the Afghan government that reinforces our commitment to the Afghan people and its security forces.

With input from our commanders on the ground, this will likely require retaining a credible, residual troop presence to help continue to thwart terrorist networks as well as provide appropriate levels of training and advice to the Afghan security forces as they continue to grow and mature into an effective, independent fighting force.

As a former small business man, I like an analogy I heard on our efforts to train and assist the Afghan Security Forces: we've helped them open for business, and now we need to ensure they have the processes and logistics in place to stay in business. Our military has a clear, understandable plan to put themselves out of business at the end of this process.

There is a shared, bipartisan legacy in Washington for Afghanistan. I am convinced history will judge both the executive branch and the legislative branch not on whether we ended wars, but how we ended them.

It is increasingly apparent that the United States left Iraq too soon, and it is with heavy hearts that we see the black flags flying in areas of Iraq where the United States expended our most precious treasure, the blood of our fellow citizens. We cannot let that happen in Afghanistan. A bilateral security agreement is critical if we're going to successfully complete the work that has been accomplished to date and to help ensure that the gains we have made are not jeopardized like they have been in Iraq.

America's foes, both state and non-state actors, are watching with great interest how we leave Afghanistan, watching to see whether we leave after securing our interests and honoring our commitments, or if we just leave.

And over the last year, our commander-in-chief has often talked more about leaving Afghanistan than how we are going to achieve our mission. We all want to bring our remaining troops home as soon as possible, but succeeding in Afghanistan is vital to our national security interests and it must take priority over any calendar dates. The President has an obligation to better make that case to the American people. And if he does, I will support him.

For more than a decade, our troops and civilian personnel have fought to bring peace and security to Afghanistan -- and to ensure it can never again be used as a safe haven for terrorists to attack the United States. Many Americans have sacrificed to secure these goals, and far too many have lost their lives or suffered life-altering wounds.

Washington and Kabul must work together to secure the gains we have made together and complete our mission.

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Why you'll be drinking toilet water soon

California's Orange County Water District (OCWD), has a plant that recycles used water and returns it to the drinking supply. It is expanding production to 100 million gallons per day, enough for 850,000 people.

At the Groundwater Replenishment System plant treated wastewater goes through a three-step treatment process using microfiltration, reverse osmosis and UV light. Pictured, reverse osmosis membrane arrays.

California's current drought is raising awareness of the value of water re-use projects, says OCWD General Manager Mike Markus.

Singapore has four water reclamation plants, although only a small proportion of the reclaimed water makes it into drinking reservoirs.

Bottled and branded recycled water, called "NEWater," is distributed to the public on some public holidays, to showcase the water quality.

NEWater meets up to 30% of Singapore's water needs. There are plans to triple the current capacity by 2060.

The recycled water is primarily used in industry. Supplied to electronics and power-generation industries, it is also piped to commercial buildings for air conditioning.

• U.S. and beyond increasingly looking to reusing sewage water for drinking


• Half the world population will face water scarcity by 2030


• Reused water is completely healthy, but psychological barriers remain


• Singapore produces large amounts of high-quality recycled water

Vital Signs is a monthly program bringing viewers health stories from around the world. This month's show looks at water and health.

(CNN) -- A third successive year of California's worst drought in a century has the Golden State's reservoirs at record lows. Agriculture has been affected, hitting the local economy, while some small communities risk running out of water.

But business is booming in California's Orange County Water District (OCWD), through a pioneering wastewater treatment facility that recycles used water -- or sewage -- and returns it to the drinking supply. The plant is expanding production from 70 to 100 million gallons per day, enough for 850,000 people, around one-third of the county population. As the OWCD output is mixed with the main groundwater supply it reaches over 70% of residents.

Sewer water recycled to tap water?

Global problem

As the shortages become more extreme and water supplies are cut, it has raised awareness that we need to find alternative resources.

Mike Markus, General Manager, Orange County Water District

The facility is among the oldest and largest of its type in the world, and could represent a model solution for a global problem. The U.N. warns that half the world population will face water scarcity by 2030, accelerated by climate change and population growth. Shortages on such a scale would threaten food production, as well as a health crisis through increased exposure to unsanitary water, which already kills millions each year through waterborne diseases such as cholera and diarrhea.

But the introduction of reuse systems has been difficult, with a high degree of public skepticism. Orange County began recycling water for non-potable use in the 1970s, but only began contributing to the drinking supply in 2008, combined with a comprehensive PR and education campaign to allay public fears.

Operators now feel the system is well established and ready to scale up. "It's a watershed moment right now, we're seeing widespread acceptance of these technologies," OCWD General Manager Mike Markus said. "As the shortages become more extreme and water supplies are cut, it has raised awareness that we need to find alternative resources."

The process works by re-routing a proportion of the 1.3 billion gallons of waste water generated in Southern California each day into a three-step treatment. The first is microfiltration of the treated waste water to remove solids, oils and bacteria, before the resulting liquid goes through reverse osmosis, pushing it through a fine plastic membrane that filters out viruses and pharmaceuticals. The water is then treated with UV light to remove any remaining organic compounds, before joining the main groundwater supply, which must pass strict quality controls to meet legal standards, and distribution to households.

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The OCWD says the water exceeds all state and federal drinking water standards. Safety has also been established in pioneering projects around the world. Water-insecure Singapore, previously reliant on imports, now delivers 30% of its needs through the NEWater reclamation facility. Although only a small amount is added to its reservoirs, the output surpasses WHO standards for potable use to the extent that a high proportion is directed for industrial uses requiring ultra-clean water.

One of the world's earliest schemes, in Windhoek, Namibia, has been in operation since 1968 and has tackled both shortage and water-borne diseases. Over half of the Sub Saharan African population faces water insecurity, and the greatest health risk, diarrhea, kills over a million people each year in the region. But research showed that in the 1970s disease occurred at lower rates for people supplied by the Windhoek plant than through conventional treated sources.

The quality from sewage is very good, as good or better than the tap water in any city in the developed world.

Benedito Braga, President, World Water Council

"Standards are stricter because of the novelty of the technology and process," says Benedito Braga, President of the World Water Council. "The quality from sewage is very good, as good or better than the tap water in any city in the developed world."

The message is now being heeded and the model is spreading. California has put $1 billion into funding recycling for potable use ($800 million of that in low-interest loans), with new initiatives launched in Los Angeles, San Francisco and San Diego.

Texas, parts of which are also severely affected by drought, aims to generate 10% of all new supplies through reclaimed water by 2060. A facility in Big Spring has introduced the first "Direct Potable Reuse" scheme in the United States by sending recycled water to the final treatment plant without passing it through groundwater reserves.

Dealing with disgust

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Clean water solutions for Haiti

In each case, public relations are key, as recycled water schemes have been historically shot down by public disgust at the concept. This was most vividly shown in the Australian city of Toowoomba in 2006 when local activists represented by the group "Citizens against drinking sewage" defeated plans to introduce reclaimed sources, citing health risks and emotive factors.

But Australia also shows the extent to which attitudes have changed. After a three-year public trial, the city of Perth will receive up to 20% of its drinking water from reclaimed sources in coming decades, with a reported 76% public support. A network of similar programs is being established across the country, according to the Australian Water Recycling Center of Excellence.

Psychologists say the aversion is deeply held and difficult -- but not impossible -- to overcome. "The disgust comes from intuitive concepts of contagion," says Dr. Carol Nemeroff of the University of South Maine, who has studied reactions to reclaimed water. "It is magical in nature, the same type of thinking that underlines voodoo practices."

"One of the best ways to get past it is perceptual cues -- if you can see sparkling fresh, clear water, and taste it that helps to overcome the concept ... the contagion type thinking decreases with familiarity," says Nemeroff, adding that necessity can also be a key driver. "If you're desperate you'll override anything for survival."

Energy and cost

In Orange County and other facilities, mixing the output with groundwater is a largely unnecessary, confidence-building measure to allay public fears. But as awareness improves, operators hope to move from indirect to direct potable reuse, which would bring down energy use and costs, while avoiding the counter-intuitive step of re-contaminating purified water.

It's the same water now as when dinosaurs walked the earth.

Melissa Meeker, executive director, Water Reuse

"The main cost is energy and that is coming down all the time," says Mike Markus. "Improvements in membrane technology allow us to use less pressure to do the same thing." The energy cost of reverse osmosis has come down by 75% since the 1970s, he says, while emerging technologies such as Aquaporin may reduce it further. Even now, the cost is favorable compared with desalination or imported water in California.

Markus hopes such advances will allow for the creation of portable modular units that can be cheaply transported to the areas of the world with the greatest need.

Campaign group Water Reuse does much of its work in education outreach, through messages such as the "Downstream" concept, that all water is ultimately recycled. "It's the same water now as when dinosaurs walked the earth," says executive director Melissa Meeker. "It's about understanding the water cycle and how we fit into it. Once people think about it, they become more open-minded."

If costs continue to fall and public acceptance continues to grow, waste water can become a major defense against the projected scarcities of this century. The World Water Council projects that recycled sewage will be a normalized source of drinking water in cities around the world within 30 years, and much of the infrastructure and technology is already in place. It's up to us now to get used to it.

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Police, protesters had tense face-off

• Ukraine PM calls for unity as he travels to riot-hit city


• PM meeting with social, political, cultural and economic leaders from Odessa region


• Forty-six people died in clashes, blaze in Odessa on Friday


• Kiev says it has launched military action to tackle pro-Moscow gunmen

(CNN) -- Ukraine's prime minister visited the Black Sea port city of Odessa Sunday, two days after a street battle between supporters and opponents of Russia ended in a deadly blaze that killed more than 40 people.

Arseniy Yatsenyuk was holding meetings with social, political, cultural and economic leaders from the region, his office said. A minute's silence was held at the start of the meeting for those who died in Friday's bloodshed.

Speaking to reporters, the prime minister called for unity as he accused those "sponsored by Russian Special Services" for the unrest in the eastern part of his country. He also said that in the last 24 hours there had been a "very active re-location of the troops from Russia to Crimea" -- which Moscow annexed in March -- but he did not provide details.

The violence in eastern Ukraine pits pro-Russian separatists against Ukrainian forces and those who support the new Western-backed government in Kiev. It has escalated into a diplomatic crisis, with Russia demanding an end to what it called Ukrainian aggression and Western powers accusing Moscow of funding the violence.

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Police: Fire kills at least 31 in Odessa

"The process of dialogue had begun, only it was drowned out by the shots from Russian-made Kalashnikovs," Yatsenyuk said of those behind the unrest in the east. "They were trying to split our people by history, culture, language, ideology, territory ... We can only win through a dialogue and unity."

Seeking to reassure a local population that has grown increasingly weary of the new leaders in Kiev, Yatsenyuk also talked about decentralizing power locally as well as providing guarantees, potentially in the constitution, for minority languages. Many in the east are Russian speakers.

"We need to preserve the country, Odessa and each human life, this is our common duty," he said.

The riot in Odessa, which ended in a fire in a besieged trade union building, was by far the worst incident in Ukraine since a February uprising that ended with a pro-Russian president fleeing the country.

Forty-six people died in the bloodshed, a spokesperson for the prosecutor's office told CNN -- six were killed in the clashes, the remainder in the fire. Of those, 32 people died due to smoke inhalation, while eight were killed trying to jump out of the burning building.

Odessa, a vibrant multi-ethnic port city, has seen some support for separatists, but nothing like the riots that erupted on Friday. Ukraine's security service blamed the unrest in the city on "provocateurs."

Video posted on YouTube appeared to show supporters of Kiev throwing Molotov cocktails at the building where pro-Russian separatists had reportedly taken up positions. The footage, which CNN could not independently confirm, showed people sitting on ledges trying to escape the fire and thick smoke.

Military action

On Saturday, a team of international military observers seized by pro-Russian separatists in eastern Ukraine was freed, as Kiev resumed military action to tackle the pro-Moscow gunmen who have overrun the region.

Ukrainian troop carriers moved into the eastern city of Kramatorsk, where some residents reported hearing gunfire, as Ukraine's embattled new leaders launched their most intensive effort yet to try to dislodge the rebels who have reportedly seized government buildings in nearly a dozen cities and towns.

A CNN team on the outskirts of the town, which is some 16 kilometers (10 miles) south of the flashpoint city Slavyansk, saw troop carriers moving toward the city center. Amateur video posted online -- of which CNN could not confirm the authenticity -- showed burned buses, plumes of smoke and residents calmly observing it all.

Saturday's release of the monitors from the Organization for Security and Cooperation in Europe resolves a major diplomatic issue for the West. Separatists had abducted the eight European observers in Slavyansk on April 25 and held them hostage.

However, in another challenge to Kiev, separatist leader Valeriy Bolotov in Luhansk declared a state of emergency and announced the formation of a "South-East" army for the entire region.

In a video statement aired on local stations, Bolotov also introduced a curfew, a ban on political parties, and his expectation that local law enforcement officials will take an oath of allegiance to the people of Luhansk.

In Donetsk, separatists say they are preparing their own referendum on May 11, to ask residents whether they want sovereignty from Ukraine -- an echo of events that led to Moscow wresting Crimea from Kiev.

Denis Pushilin, the self-declared chairman of the Donetsk People's Republic, told CNN the question to feature on the ballot paper would read: "Do you support the act of state sovereignty of the Donetsk Republic?" to which voters can respond with "Yes" or "No." He said enough ballot papers had already been printed to hold the vote.

Separatists, many of them of Russian descent, believe the government in Kiev is illegitimate, since it formed after what they call the illegal ousting of pro-Moscow President Viktor Yanukovych in February. Officials in Kiev accuse Moscow of meddling with its support of separatists.

NATO has estimated up to 40,000 Russian troops are now near the border with Ukraine, which has made not just Kiev's government but other neighboring nations wary of invasion.

Russia and the West squared off diplomatically over the fate of Ukraine after Moscow annexed the Black Sea peninsula of Crimea in March following a hastily called referendum and Yanukovych's ouster. He was pushed from office after months of protests by people upset that he had turned away from Europe in favor of Moscow.

Russia has condemned Kiev's military action in the volatile east.

In a phone call Saturday with U.S. Secretary of State John Kerry, Russian Foreign Minister Sergey Lavrov said: "(The) punitive operation in the southeastern Ukraine plunges the country into fratricidal conflict."

Dmitry Peskov, Russian President Vladimir Putin's spokesman, said Russia's government had received thousands of calls since Friday from people in southeastern Ukraine. The callers described the situation as "horrendous" and pleaded for Russia's involvement. "Most of the people literally demand active help from Russia," he said.

Nick Paton Walsh, Claudia Rebaza and Jo Shelley contributed to this report.

Be afraid to breathe air

A 2014 report ranks cities that have the worst air quality. San Francisco, California, is among them.

Downtown El Paso, Texas

A plume of exhaust rises from a coal-fired power plant located 20 miles southwest of Pittsburgh, in New Eagle, Pennsylvania.

Los Angeles, California, seen through smog before sunset.

Fairbanks, Alaska

• A new report lists the cities that have the worst air quality in the U.S.


• Dan Farber: Part of the problem stems from policy failures in Washington


• He says we need to implement mass transit more on a national level


• Farber: Air pollution from cars and trucks pose a real public health hazard

Editor's note: Dan Farber is the Sho Sato professor of law at the University of California, Berkeley, where he is also the co-director of the Center for Law, Energy and the Environment. The opinions expressed in this commentary are solely those of the author.

(CNN) -- A new report from the American Lung Association lists the cities that have the worst air pollution in the U.S.

Places in Southern California and the Central Valley, including Los Angeles, Fresno, Visalia and Modesto, top the list. But Las Vegas, Salt Lake City and even Fairbanks are also offenders.

Part of the problem stems from policy failures in Washington. Of course, local governments are at fault as well.

In California, cars and trucks contribute heavily to the problem, as is also true in cities like Dallas. LA pioneered urban sprawl and the car culture and is now paying the price. But it's not alone: Atlanta, Charlotte, and others are also sprawled across the countryside.

American cities have not done enough to get people out of cars and onto mass transit. LA exemplifies the problems. As detailed in "Railways," a recent book by Ethan Elkind, LA focused too much on subways and not enough on trolleys and dedicated bus lanes. To make matters worse, the routes were often in the wrong places due to political interference from the city council through the state capital to Congress.

It's not realistic to expect that something as major as transportation infrastructure will be immune from politics, but rational planning needs to play a bigger role than it has in the past. LA's specific problems were its own, but mass transit is in need of more support and better implementation across the nation. All too often, support for mass transit is portrayed as a wasteful subsidy because its benefits to the public are misunderstood.

The federal government has sometimes failed to do enough to fight air pollution. Under the Bush administration, especially, industry succeeded in using federal laws as a shield against state regulation. For instance, cities have been blocked from addressing pollution from older, dirtier trucks.

When one port authority tried to prohibit dirtier trucks from using its facilities, the Supreme Court held this effort violated a federal law deregulating prices and routes in the trucking industry. It was probably a surprise to Congress that the effort to allow markets to control this industry gave the industry special immunity from the kinds of pollution regulations that apply to every other industry. Obviously, other cities also have their own high-polluting trucks, and they are similarly stymied.

Lawsuits have also prevented cities from modernizing fleet vehicles such as cabs. When one West Coast air quality district tried to make fleet vehicles such as cab companies buy only the cleaner vehicles on the market. Although this would have been a significant step toward improving air quality in a heavily polluted area, the Supreme Court ruled that the air district was violating federal law. This ruling has had ripple effects elsewhere in the country, like New York City, where federal courts have blocked efforts to upgrade its cab fleet.

Some say electric cars are the future. But when electric cars were first introduced, the Bush administration took the very unusual step of getting involved and siding with industry. It wasn't until Bush left office that California was able to make a bigger push for electric cars. The delayed introduction of electric vehicles is bad for the U.S.

State regulators, even with the best intentions, can't go it alone. They need local governments to help combat sprawl and support mass transit.

The Environmental Protection Agency has an obvious role to play in addressing pollution, and it needs to be more effective. New federal regulations on pollution from electric power plants are a long-overdue step in the right direction. Hopefully, EPA will also tighten ozone standards during its next review. But at the same time that the federal government is trying to do more, it is ironic to see federal law used to block state pollution controls.

Air pollution these days is a deceptive problem. People know that some days are hazy and leave their eyes irritated. What they don't realize is that these problems are only the tip of the iceberg. Air pollution results in more respiratory illness, more trips to the ER, and more deaths. According to EPA estimates, its program to reduce cross-state pollution (which the Supreme Court upheld recently) will save 14,000-34,000 lives per year. We've made real progress should not become complacent over this major public health issue. We need to redouble our efforts.

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