Michelle Cottle is right about this: The dysfunctional dance taking place in the House between Speaker Kevin McCarthy and his right flank has driven me to consider something I never imagined possible: that Matt Gaetz is right. A House speaker can be successful only with the confidence of the members who put him or her in charge, when he or she can follow through on promises made and concessions extracted. Indeed, there may be no job in American government that calls for crackerjack deal-making skills more than that of speaker: so many egos, alliances and grievances to manage to keep things moving. Mr. McCarthy, in his desperate pursuit of the speakership last winter, ran around making promises willy-nilly to the House’s small band of right-wingers, and he will now rise and fall on how he handles those commitments and expectations. So far, things are not looking good for Kev — and, by extension, for a functional Congress. Miffed at the speaker’s handling of the spending fight, the right’s hard-liners have been threatening to oust him, shut down the government or both. His attempt to placate them by announcing an impeachment investigation into President Biden went over poorly, prompting multiple Freedom Caucusers to scold him for trying to buy them off. Mr. Gaetz, the Florida congressman and frontman for the rebels who temporarily blocked Mr. McCarthy’s speakership in January, dismissed the move as a disingenuous “baby step,” accused him of being “out of compliance” with his commitments to hard-liners and threatened to force daily votes to…