Does the political class overrate the necessity of diplomacy experience in presidential candidates? n a strange convergence, there's agreement among the diehard right-wingers gathered at the Conservative Political Action Conference outside of Washington this week and left-wing pundits: Scott Walker is on top of the world. Well, maybe not the world—we'll get to that—but the Republican presidential sweepstakes. Although Jeb Bush boasts impressive momentum—nearly insurmountable momentum, in the judgment of D.C. tastemaker Mike Allen—CPAC is a good illustration of Bush's weaknesses. Bush was due to speak later Friday, but just the mention of his name drew boos earlier in the...