Policies to promote biofuels are extensive. The political rhetoric justifying them typically takes one of three forms. The first is to support farmer wealth. The desire to protect US farming jobsand profits has been a popular political objective for quite some time, and biofuel policies fitunder a larger umbrella of related policies, such as price supports. The second is to reduce our dependence on foreign oil. And the third is to reduce greenhouse gases (GHGs). Since the oil shocks of the 1970s, US policymakers have expressed a constant desire to reduce our dependence on foreign oil. This desire appears to have strengthened in the last two decades, as war efforts in the Middle East have increased. Americans' concern over climate change has also increased in that period, leading many policymakers to support GHG-reducing policies.