But here is a pretty good rule of thumb for Democratic Presidents: if it didn’t work for Franklin D. Roosevelt, who won four terms and a World War, it probably won’t work for you either.

In one of the rare political debacles of his long life, FDR overreached after his landslide win against Alf Landon in 1936. (Roosevelt carried every state, save for Maine and Vermont.) A largely conservative Supreme Court had already struck down key parts of New Deal legislation, and there was the threat of more anti-Roosevelt decisions to come. And so FDR proposed a plan that would have enabled him to appoint additional justices in an attempt to shift the court’s political orientation. The effort failed, miserably.

Justified or not, the Supreme Court has a kind of sacred status in American life. For whatever reason, Presidents can safely run against Congress, and vice versa, but I think there is an inherent popular aversion to assaults on the court itself. Perhaps it has to do with an instinctive belief that life needs umpires, even ones who blow calls now and then.