Good politicians, like Ike and JFK (and yes, our Bill Clinton), use the landscape around them to shape coalitions that sustain them in power. Great politicians, like Reagan and Franklin D. Roosevelt, refashion the landscape, creating realignments that survive them by decades.

Obama, by contrast, has done something different: He first formed, and then shredded, his own coalition, creating wedge issues that splintered his party, with no help from opponents at all.