Among right-wingers, there has been some delight about polls showing that Joe Biden's popularity at the 100-day mark is the lowest of any president since World War II. Oh, if you exclude Donald Trump. Undaunted by this detail, they note with satisfaction that Biden's approval rating, according to multiple polls, is somewhere between 52 and 57%. At this point in his presidency, Trump's approval was 40%. Americans were far less partisan in the era of Eisenhower, Reagan, Bush and even Clinton than they are now. Large numbers of Democrats were willing to give high marks to Eisenhower when the economy...