Those who insist on characterizing the president as a fringe figure ought to confront an important challenge: Name one significant policy or appointment during his first term that would have been inconceivable for Mrs. Clinton—or for Messrs. Biden, Edwards, Dodd, Richardson or the other leading Democratic presidential alternatives.

The commonly recycled notion that President Obama has “surrounded himself with socialists”—giving key appointments to leftist activists and academics from outside the D.C. establishment—remains utterly unsupported by the evidence. Among the 15 cabinet officers, the majority (eight) had previously won election as Democrats (or Republicans) to the Senate, House or, in four cases, governorships (three of them from red states). The rest include three senior holdovers from the Clinton or Bush administrations, two department heads from New York and Chicago city government, a four-star general of the Army and a Nobel Prize winner in physics who previously headed the Energy Department’s top research lab.

One can scan the list of leading appointments (including Mr. Obama’s two chiefs of staff, one a former congressman and the other a former Clinton cabinet officer) without finding a single example—not one—of the sort of wild-eyed, revolutionary intellectual frequently cited by right-wing critics.