The debate over a national renewable energy requirement has lost its way. Perhaps one of the most important legislative proposals in recent memory because it could transform the United States’ energy infrastructure, this “renewable portfolio standard” or “RPS” would likely compel electric utilities to obtain one-fifth of their power from renewable resources. Yet the discourse over this proposal has veered from the core question it raises. With thirty-six state RPSs already in place, the key issue is not whether there should be an RPS at all but whether a state or federal regime will best accomplish the RPS’s objectives. This Article concludes that the evidence overwhelmingly points to the need for a national law. The Article reaches its con...