The major obstacle to progressive environmental policy is not the GOP-controlled Congress, nor is it the Koch brothers' political contributions. Rather, is it the U.S. military. Let me explain.

We in the United States take war for granted. It is, simply, what nations do. And superpowers do war very well. According to the International Institute for Strategic Studies, the 2013 defense budget of the United States was $600.4 billion, more than the next nine top-spending nations combined. (China held second place at $112.2 billion.)

The U.S. Department of Defense is the single largest consumer of energy. Ninety-three percent of U.S. government energy consumption is military (Air Force, 52 percent; Navy, 33 percent; Army, 7 percent). Energy consumption includes 30,000 gigawatt hours of electricity valued at $2.2 billion (enough to power 2.6 million average American homes for a year). The Defense Department used 4.6 billion U.S. gallons of fossil fuel annually — 12,600,000 gallons per day. If the U.S. military were a country, fuel consumption would rank 34th, just behind Sweden.

Put in perspective, Gen. Patton's army in World War II consisted of 400,000 GIs and consumed 400,000 gallons of gasoline per day. In Iraq in 2005, we had one-third as many troops but consumed four times the fuel. Today's B-52 bombers consume 3,300 U.S. gallons per hour, and the F-16 fighter uses 800 gallons per hour. War and the tools of war consume more fuel than ever before, and consumption continues to increase. And it's expensive: While ordinary Americans pay between $2 and $4 per gallon for gasoline, U.S. taxpayers pay $45 per gallon to purchase, deliver and protect fossil fuels supplied to our war zones.

The environmental impact of fossil-fuel consumption is immense. While former Vice President Al Gore's book "An Inconvenient Truth" asks each of us to reduce our carbon footprint, the even more inconvenient truth is the role of our military in exacerbating fuel consumption and the consequent environmental crisis. We shame individuals but excuse the system and its policymakers.

More than 20 years ago, I attended an environmental conference at the University of Denver. At a session of 500 attendees and a panel of experts, an elderly gentleman chided the panelists, saying, "Look at you hypocrites! You talk about protecting the environment but you sit there drinking water from Styrofoam cups!" The director of the Colorado Environmental Protection Agency responded: "Your criticism is misdirected. We panelists are guests of the university. Whether any or all of us refuse to drink from a Styrofoam cup would have a negligible impact on the environment. You should direct your concern to the university and ask policymakers to quit using Styrofoam, or lobby the city or the state. The problem is systemic, but your objection is individual."

The inextricable connection between the military and the environment doesn't end with fossil-fuel consumption. The Defense Department is also the largest producer of toxic waste and toxic-waste sites in need of cleanup. The U.S. military generates 750,000 tons of toxic waste annually, more than the five largest U.S. chemical companies combined, making the U.S. military the world's largest polluter.

This provides another inextricable link between war, the environment and racism, since most toxic-waste sites are on American Indian reservations or in major metropolitan areas typically among the urban poor, who, in our country, tend to be people of color. Such environmental racism is driven by preparation for and execution of war.

The argument is simple and the conclusion unavoidable: If we care for the health and sustainability of our environment, then we have no choice but to reduce U.S. preparation for and involvement in war. Of course, doing so will not solve all of our environmental problems, but it will be a necessary step in the right direction if we are to leave a healthy and sustainable environment to our children and grandchildren.

Duane Cady, of Roseville, is a retired college professor.