Forty-three men between 1789 and 2017 demonstrated the awesome and growing power of the American presidency. Sometimes they were blunt, other times much more deliberate. But in 2017, something shifted, and since then we've seen how extremely fragile the presidency is, too. The two men who've held the office since then have exposed its frailty over and over again. One battered norms with open contempt, mistaking spectacle for strength and grievance for governance. He treated institutions as obstacles to be humiliated into submission. The other stretched executive authority past its snapping point in the name of restoration, governing through emergency and exception. Then that first guy came back, but worse, and that's where we are now. Whether through chaos or consolidation, they both marked radical departures from the managerial, post-Cold War presidency. They weren't course corrections -- they were disruptions. Joe Biden and Donald Trump: the Aberration.