I am going to be busy during the early part of the day helping my mother get my Dad to a doctor’s appointment, but I wanted to open a discussion which I can pick up when I get back. The question is, what explains Joe Biden’s rather steep decline in the polls in the latter half of 2021?

Here’s one effort to answer that question from Jonathan Chait.

Nobody can say with any confidence if this fall can be reversed. Indeed, given the U.S.’s steady job growth, nobody can ascertain exactly why the public has turned so sour so fast. Biden is like a patient wasting away from some undiagnosable disease. What is clear is that if the presidential election were held this fall, Biden would enter the contest as the decided underdog against Trump.

The conventional wisdom has deemed that Biden is getting his just deserts for trying to govern as a liberal…

But the truth is that Biden’s presidency began to disintegrate without his abandoning the center at all. He found himself trapped instead between a well-funded left wing that has poisoned the party’s image with many of its former supporters and centrists unable to conceive of their job in any terms save as valets for the business elite. Biden’s party has not veered too far left or too far right so much as it has simply come apart.

I agree that Biden would lose an election to a Republican right now, possibly including even Trump, and I agree that “a lot of people are saying” that this is because Biden’s gone too far to the left. I think, however, that there’s more to it even if, as Chait suggests, it’s currently undiagnosed.

Chait’s explanation has a nice symmetry to it and plenty of surface plausibility, but I think it’s probably just a bit too tidy. There are obviously some things, like the withdrawal from Afghanistan, supply chain disruptions, and the Delta variant of COVID-19 that have something to do with Biden’s approval numbers. It’s not all about “Dems in Disarray.”

Yet, divisions within the party are most exposed when the majorities in Congress are tight. It really limits Biden to what can be done rather than fine-tuning to get the best political response.

Anyway, how do you weight the factors?