From Al Gore to Lester Brown, writers concerned about preventing the worst of global warming have proposed that our “commitment will need to be of a scale comparable to what we did during World War II.” But the parallels never go beyond a vague reference.

PBS is about to run a series, premiering this Sunday, called “The War,” so it might be a good time to think a little more deeply about the connection.

There are two main questions that need to be asked: Is global warming — or more generally, the assault on the biosphere, including the wholesale destruction of ecosystems and species — an emergency, as was World War II? In other words, do we have to do something quickly? Second, what was done in World War II to meet the emergency, and what lessons can we learn from that response?

I’ll start with the second question: the federal government virtually took over the economy during World War II. The U.S. had a tiny military — I remember reading that the army was 17th in the world, behind Bulgaria — and it had to be ramped up as quickly as possible. Believe it or not, the CEOs of the auto companies met with President Roosevelt and agreed not to make cars for the rest of the war. Instead, the car companies and the rests of the industrial sector set about to make tanks, planes, boats, bombs, guns, and bullets instead.

Can you imagine a U.S. president summoning the car companies into the Oval Office, forging an agreement to stop making automobiles for five years, and instead convincing them to pump out high-speed rail, light rail, trolley rail, and buses? Can you imagine construction companies agreeing to not put up any more single-family houses, but instead putting up Platinum LEED near-zero-emissions apartment buildings and commercial buildings, each with geothermal exchange systems for heating and cooling and solar roofs for electricity? What if road construction companies agreed not to pave any more space, and instead built the rails for the new rail systems? And what if the coal companies and nuclear energy companies agreed to work with GE and others to put up only wind power and solar thermal farms? What about ADM and ConAgra agreeing to help the agricultural sector eliminate the use of artificial fertilizers, pesticides, and factory farming?

Those more-than-unlikely scenarios would be the equivalent of “what they did in World War II.” Not cap-and-trade or cap-and-auction, not carbon taxing, not fuel-efficiency standards. Can you also imagine what would have happened in World War II if Roosevelt had tried to fight the Japanese and Germans by raising a consumption tax so that a small percentage of the federal budget could be put into researching how to fight the Axis powers? Or tried to free up enough resources by increasing the efficiency of appliances and cars? Or perhaps they could have capped and traded military equipment? We’d either still be fighting in the Pacific, or my NYC-born parents would have wound up in concentration camps and you wouldn’t have been able to read me rant about this.

So, are we in a true state of emergency? I’m currently reading Fred Pearce’s new book, With Speed and Violence, and his warning signs have certainly been in the news, such as the thawing of the Soviet tundra and the melting of the Arctic, which are dangerous because of the positive feedback aspects of these changes. How many years do we have? Does James Hansen still think we have 10 years, or has it been a couple of years since then, so it’s now more like eight? Do we need to start moving now? Or do we really have more like 20, or even 30 years?

If you think we really have to move now, I suggest you read up on the American economy during World War II, because it really is the best example of transforming an economy quickly — and the government’s investment in and direction of the economy was front and center.