Anyone who cares about our natural environment should be marking with great sadness the centenary of World War I. Beyond the incredible destruction in European battlefields, the intense harvesting of forests, and the new focus on the fossil fuels of the Middle East, the Great War was the Chemists' War. Poison gas became a weapon -- one that would be used against many forms of life. Insecticides were developed alongside nerve gases and from byproducts of explosives. World War II -- the sequel made almost inevitable by the manner of ending the first one -- produced, among other things, nuclear bombs, DDT, and a common language for discussing both -- not to mention airplanes for delivering both. War propagandists made killing easier by depicting foreign people as bugs. Insecticide marketers made buying their poisons patriotic by using war language to describe the "annihilation" of "invading" insects (never mind who was actually here first). DDT was made available for public purchase five days before the U.S. dropped the bomb on Hiroshima. On the first anniversary of the bomb, a full-page photograph of a mushroom cloud appeared in an advertisement for DDT. War and environmental destruction don't just overlap in how they're thought and talked about. They don't just promote each other through mutually reinforcing notions of machismo and domination. The connection is much deeper and more direct. War and preparations for war, including weapons testing, are themselves among the greatest destroyers of our environment. The U.S. military is a leading consumer of fossil fuels. From March 2003 to December 2007 the war on Iraq alone released more CO2 than 60% of all nations. Rarely do we appreciate the extent to which wars are fought for control over resources the consumption of which will destroy us. Even more rarely do we appreciate the extent to which that consumption is driven by wars. The Confederate Army marched up toward Gettysburg in search of food to fuel itself. (Sherman burned the South, as he killed the Buffalo, to cause starvation -- while the North exploited its land to fuel the war.) The British Navy sought control of oil first as a fuel for the ships of the British Navy, not for some other purpose. The Nazis went east, among several other reasons, for forests with which to fuel their war. The deforestation of the tropics that took off during World War II only accelerated during the permanent state of war that followed. Wars in recent years have rendered large areas uninhabitable and generated tens of millions of refugees. Perhaps the most deadly weapons left behind by wars are land mines and cluster bombs. Tens of millions of them are estimated to be lying around on the earth. The Soviet and U.S. occupations of Afghanistan have destroyed or damaged thousands of villages and sources of water. The Taliban has illegally traded timber to Pakistan, resulting in significant deforestation. U.S. bombs and refugees in need of firewood have added to the damage. Afghanistan's forests are almost gone. Most of the migratory birds that used to pass through Afghanistan no longer do so. Its air and water have been poisoned with explosives and rocket propellants. The United States fights its wars and even tests its weapons far from its shores, but remains pockmarked by environmental disaster areas and superfund sites created by its military. The environmental crisis has taken on enormous proportions, dramatically overshadowing the manufactured dangers that lie in Hillary Clinton's contention that Vladimir Putin is a new Hitler or the common pretense in Washington, D.C., that Iran is building nukes or that killing people with drones is making us safer rather than more hated. And yet, each year, the EPA spends $622 million trying to figure out how to produce power without oil, while the military spends hundreds of billions of dollars burning oil in wars fought to control the oil supplies. The million dollars spent to keep each soldier in a foreign occupation for a year could create 20 green energy jobs at $50,000 each. The $1 trillion spent by the United States on militarism each year, and the $1 trillion spent by the rest of the world combined, could fund a conversion to sustainable living beyond most of our wildest dreams. Even 10% of it could. When World War I ended, not only did a huge peace movement develop, but it was allied with a wildlife conservation movement. These days, those two movements appear divided and conquered. Once in a blue moon their paths cross, as environmental groups are persuaded to oppose a particular seizure of land or military base construction, as has happened in recent months with the movements to prevent the U.S. and South Korea from building a huge naval base on Jeju Island, and to prevent the U.S. Marine Corps from turning Pagan Island in the Northern Marianas into a bombing range. But try asking a well-funded environmental group to push for a transfer of public resources from militarism to clean energy or conservation and you might as well be trying to tackle a cloud of poison gas. I'm pleased to be part of a movement just begun at WorldBeyondWar.org, already with people taking part in 57 nations, that seeks to replace our massive investment in war with a massive investment in actual defense of the earth. I have a suspicion that big environmental organizations would find great support for this plan were they to survey their members.