Okay, some backstory.
Buchanan may have been a closeted gay man, was a foreign diplomat and, of course, oversaw the bleeding wound that was Kansas, Dred Scott, and the secession of SC itself. He was picked for president because he very conveniently had been out of the country while the compromise of 1850 was slowing coming apart. In other words, party bosses picked a guy because he dodged hard questions, the sort of reasoning that doesn’t work so well on the other side of things.
Buchanan is obviously a racist, proslavery person but is not so idiotic as to openly promote such. The problem is that racist gay president probably does get figured out and thrown into scandal with today’s omnipresent media. Buchanan would, given the times, admit that his opinions were misguided.
Buchanan was primarily a weak man, too easily made to follow majorities and powerful interests. This would put him comparably to GW Bush. Buchanan does not antagonize NATO, withdrawal from bargains made with Iran or the Paris climate accords, he’s more likely to sign TPP and do what powerful lobbies tell him to do. Ironically, these lobbies may very well not desire the ‘Trump Tax Cuts’ and they may not happen.
Donald Trump came to office with majorities in the House and Senate. Buchanan, who may very well have the same setup, may opt to simply fund infrastructure bills and unimaginatively keep the US going. At this point, Buchanan’s cabinet being wildly different from Trump (Buchanan would definitely count as a ‘Southern Democrat’ in his ideological thinking) is functionally competent and capable, if bland.
This does a lot of good in being forgettable, quietly doing their jobs, and not being a problem.
Eventually some idiot decides to kill a bunch of people in an act of deranged gun carnage. This country can not go more than 100 days without an act of deranged gun carnage. This is another faultline, and its one where Buchanan doesn’t really give a strong response.
This all puts Buchanan in December 2019 in a lousy spot. He’s not popular, he’s not the man for his time, the media is hostile. And then a Coronavirus emerges in Wuhan…
On one hand, this is the previous president who took little action as a pandemic of violence was ripping the nation apart. On the other, there is no powerful lobby looking for COVID to kill as many people as possible, and Buchanan is primarily the victim of, not the champion of conspiracy theories. It’s not his personal nature, but Buchanan is empowered to be bold, strong and decisive on action. Privately, he has zero medical training but he’s intelligent enough to let those people who do have their say.
The reality is Buchanan is screwed; with a media narrative against him, always playing catch up and damage control, and not having any hard base of people who love him, he is going down to defeat.
In Buchanan’s defense, the easy call is the right call. Masking is mandated immediately; delusions and conspiracy theories are already facing an administration hostile to their progress. With federal efforts behind it, some states (Texas, Florida) sulk about federal overreach but comply. Buchanan is also acutely aware that he needs some victories, and trying to moonshot a COVID Vaccine becomes the great mandate of his response. Indeed, in a series televised speeches, President Buchanan partially rehabilitates himself. A Covid Vaccine being found before election day is perhaps the best argument to vote for re-electing Buchanan, but a bland scandalprone gay man is a couple of bridges too far.
Buchanan instead opts not to run again.
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So what’s the score?
The United States is still a superpower and respected around the world. Four Years of President Buchanan have made it stodgier and a little out of touch, but decades of civil servants have continued their duty in spite of far worse.
At home, the economy is not going great, as COVID would indicate. True, the Vaccine is out, although the hurdles of getting hundreds of millions of doses take time. Buchanan would not like the structural deficits the US has as of 2017, so I imagine he’d get a moderate set of tax hikes. This doesn’t do much to hurt the economy, and ironically means the US has a bit more resources to try to address the economic impact of COVID, but moderate tax hikes aren’t panaceas.
James Buchanan ultimately does find a few hard supporters of what he did, probably because of the success of finding a COVID vaccine. This could be very far afield of where he lived (Pennsylvania) and builds a presidential library. In a scene that he’d never thought he’d know, he marries another man and becomes an improbable advocate of LGBT causes.
History probably decides to put Alt-Buchanan above presidents Harding and Nixon, mostly given that he wasn’t abjectly terrible.