Back in August, we caught Joe Scarborough predicting that President Trump won't seek re-election in 2020. Scarborough stuck to that problematic prognostication this morning in offering an explanation for Nikki Haley's resignation as UN Ambassador.

Joe conjectured that Haley is positioning herself to run in 2020—and to get out in front of Mike Pence—after Trump decides not to run.

JOE SCARBOROUGH: You know, Willie [Geist], there was, there's always been talk about Nikki Haley running—possibly running in 2020—David [Ignatius] is talking about 2024. If my theory holds, Donald Trump won't seek re-election, and this way, she's not lining up behind Mike Pence, she's getting out in front of everything. And if you get out before the mid-term elections, which could possibly go pretty badly, well, then that stain's not on you -- you were already on your way out.

It wouldn't be surprising to learn that Haley harbors White House ambitions. But the big blip in Scarborough's scenario is the notion that Trump won't seek re-election in 2020.

Assuming: 1. Trump's apparently robust health holds; 2. Republicans hang onto a Senate majority, giving Trump the chance to cement his legacy through another SCOTUS nomination; and 3. the economy stays strong, it seems virtually inconceivable that the President wouldn't seek re-election.

Even if the Dems retook the House majority in 2018 and commenced impeachment proceedings, you would think that would only inspire Trump -- the ultimate counterpuncher -- that much more to defeat them and his Dem prez opponent.

Willie Geist dragged out the favorite liberal scenario, she would run "as a safety valve, if something comes up in the Russia investigation, for some reason, he does not run again, she can be there."