Ezra Klein's post on Trump reads like a thorough and wholly effective take-down. Until, that is, you get to the end, where he says that Trump should be disqualified "because the presidency is a powerful job where mistakes can kill millions, and whoever holds it needs to take that power seriously and wield it responsibly." Klein, and many other liberals besides, neglect to mention the atrocities perpetrated on the watch of a number of other more "serious," "rational," and "hard working" American presidents.
Recall Nixon's war in Vietnam; Reagan's military excursions in Latin America; Bush's crusade in Iraq and Afghanistan and the continuing fallout; and Obama's doubling down on Bush's failed policies and the uptick in drone warfare in Pakistan and elsewhere in the Middle East.
The point is that America isn't so much in the habit of putting in power the serious and venerable figures Klein has in mind. Trump's just more transparent and brazen in his disregard for the niceties that go along with implementing American hegemony at home and abroad.