LAWMAKERS TACKLING the National Defense Authorization Act are understandably focused on figuring out the dimensions of the president's right to detain terrorism suspects and whether those suspects should be held in the mainland United States. But there's another important issue that's come under debate — the Defense Department's investment in renewable-energy technologies. So far, the Pentagon's biofuel efforts have survived two Senate challenges, which is good news for the Pentagon, the environment, and innovation.

For years, the Pentagon has been testing new sources of energy to decrease the military's dependence on oil. As the world's largest institutional consumer of fossil fuels, the Pentagon's interest in new technologies helps create a market for clean energy. The military's support for biofuel research is not merely a matter of good conscience, but also of good security policy, given the instability of oil prices and imports.