Trump is having a lousy week. You've probably heard. The President's Charlottesville response was deemed inadequate, his lawyer has been forwarding misguided General Lee comparisons, and now we've learned that a crown jewel of Presidential gatherings - the lauded Manufacturing Council - is no more. Who knew condemning Neo-Nazis could be so hard?
This latest raft of negative press likely won't help the President's declining popularity. FiveThirtyEight has Trump's approval rating at a lowly 37.3%. The site's nifty historical comparisons also show that, among post-WW2 Presidents, only Gerald Ford had a similarly poor approval rating at this point in his administration. Trump's North Korea Twitter rhetoric certainly doesn't alleviate concerns about executive or national stability either.
However, while Trump's low rating is unusual given how early we are in his administration, it is not really an outlier in the context of overall Presidential approval:
Many Presidents have, for instance, dipped below 40%. Precipitous drops in popularity are the norm rather than the exception - although they do tend to occur in a President's second term. Trump's fall is particularly jarring compared to Barack Obama's rather serene eight years, an historic outlier that featured no true "bottoming out" a la Nixon, Carter, or either Bush.
Still, does Trump's miserable approval rating mean he won't be re-elected? To investigate, I plotted the approval of first term Presidents by the number of days until their re-election bid, splitting out winners and losers. The 1964 election run-up is shown for LBJ.
It's clear that incumbents usually win. Only Ford, Carter, and George H.W. Bush lost their re-election bids. Voters generally prefer the devil they know.
The other noteworthy trend is that early term Presidential approval is not a good predictor of election success. Clinton was exceptionally unpopular at times. And Truman's swings over the course of his first term make Trump's administration look positively uneventful. Trump is certainly in bad shape, but it's not inconceivable he turns it around.
Of course, I do realize a President must actually make it to the election to be re-elected.
P.S. It is worth mentioning that approval rating has some severe flaws: first, the question is rather vague - why not ask a respondent directly about the President's effect on their quality of life? Second, military action tends to give administrations a nice boost (at first). This is a sub-optimal incentive structure. The metric reminds me of batting averages in baseball: no student of the game takes them seriously, but since even the layperson knows the definition it is unlikely that Mendoza line mentions ever fall completely out of favor.