Yeah, totally boring academic title, but there's a point to it. Here in this online community, we tend to err on the side of rational analysis, and I'm going to be a stinker and point out how much politics shapes what passes for rationality. For example, if we were a rational species, there wouldn't be 20 million-odd people in Southern California where I live, because the area's semi-desert at best, and the only way people can live here is to have water pumped in from hundreds of miles away. If history and archaeology are any guide (going back to Mesopotamia), cultures that relied on long-distance irrigation have inevitably fallen when their water systems failed, and there's no reason to think southern California will be any different. So why are there so many people in this evanescent "paradise" that is southern California? Politics. Politics turns rational proposals, such as John Wesley Powell's 19th Century rational proposal to dam some western rivers and irrigate a bit of farmland, into the unsustainable sprawl of pork-barrel dams and water works that is the American West today. That's why I'm talking about political economy, not just economics: this isn't just about money, it's also about political power. That's what makes it more interesting, complex, and yes, irrational.
Speaking of rational proposals for restructuring civilization, there's one out there, by Stanford engineering Professor Mark Jacobson. He proposes that, by 2050, the US can supply its power needs entirely through renewable sources: photovoltaics, solar thermal, wind, waves, and hydroelectric dams (see The Solutions Project, among many others). Here I'm not going to analyze Dr. Jacobson's proposal in much detail, because most of you are more tech savvy than I am, and you're perfectly capable of doing that yourselves. What I'm more interested in is what politics could do to this rational proposal, and what kind of an America would result.