LyrArc Article Gist
Krugman points out that in American history even presidents who did not read much and were not very qualified were able to perform well in office because of very qualified people in the cabinet positions. Reagan was not a avid reader yet he had Shultz at State and James Baker at Treasury. Mnuchin is not anywhere near being qualified as James Baker. Tillerson may be qualified as a CEO of a large energy company, but lacks the experience of Shultz. During the last years of his presidency Reagan may have felt the effects of early Alzheimers. Checks and balances also helped to make the system work under presidents so that they did not overreach their powers. 

Krugman is skeptical of the way checks and balances would work under president Trump and sees some second rate appointments in the administration. He points to the departure of Mike Flynn and the controversies surrounding the Russian meddling as very different from the situations faced by other presidents with weak qualifications.