Remember what happened in 2004/2005?
The Republicans won that election. Bush was re-elected narrowly but solidly; they gained seats in the house and had a narrow majority in the Senate. The president commanded respect within the party. The economy was doing well. They claimed they had a mandate. The first thing they chose to do with it is go ahead and try to privatize social security.
It blew up on their faces. Bush just could not get enough legislators to even consider the idea. It never got a vote even in committee, after months of huffing and puffing. Other planks of the party platform quickly fell by the wayside once the Iraq war started going South.
OK, social security is a very popular program, it was a second-term president, and so on. Maybe not the best example.
Let’s look back at 2009, then. Obama just won big, and dems have both the house and the senate. The VP is an experienced, relatable, competent former legislator. POTUS is a god-like level politico at the height of his powers. The Speaker is one of the best legislators in the House. Harry Reid is also a great negotiator. They get the stimulus done with some GOP support, and then they tackle the holy grail of progressive politics, something that the democrats have been chasing since the days of Teddy Roosevelt: health care reform.
This is something that in theory unites the party. The leadership team is highly competent. It is a popular issue (health care reform was very popular in 2008). Even with all that in favor, getting the ACA across the line pretty much tore the democratic party apart. They barely got the bill through, and then proceeded to get soundly trashed in the mid-terms. The only relevant piece of legislation passed after the ACA was Dodd-Frank, and it was something beating up the banks right after a financial crisis.
Now consider Trump. He narrowly “won” the election (he will lose the popular vote by a larger margin than Bush in 2000). They have lost seats both in the House and the Senate. The party establishment doesn’t really like the POTUS, and he doesn’t have any meaningful legislative experience. His VP was in the House for years, but he never managed to get one of his bills passed. The House caucus has been a madhouse for years, to put it mildly, and the Speaker is reviled by the trumpist. They do have a disciplined and well-led Senate, but that’s about it.
Trouble is, Trump’s agenda is not one that could keep most of the party united for long. Infrastructure will anger the deficit hawks in the caucus. For what I’ve been reading, the President has a surprising amount of executive leeway on trade levies, but the GOP as a whole is still pro-trade.
Immigration, though, is the real landmine here. Although opposition to reform is very loud, most Republican voters favor a path to citizenship for undocumented immigrants. The party elites are pro-immigration. Bush had a reform proposal fall apart in 2007; Obama had one fail in 2013. I’d be really surprised if Trump, a guy not known for its subtlety, brings a proposal forward and then manages to trigger a horrible mud fight in the House on this issue, with Democrats standing by.
Other issues might be less fraught, but they are still hard to get through. Republicans, to this day, don’t have anything close to an ACA alternative bill. They cannot just repeal it as quite a few pieces of the law are popular (pre-existing conditions, for instance), so they need some form of repeal-and-replace. Good luck getting one without a big fight. Trump’s tax cuts, as written, have a hefty middle-class tax increase. That might generate a fight, as well. Then we have the whole Paul Ryan entitlement reform agenda. Social security remains toxic, and Trump promised not to cut Medicare.
My gut feeling is that the Trump presidency will go as follows. First, he will do a horrific amount of damage repealing executive orders (remember all those global warming questions they got during the debates?). He will get one Supreme Court Justice in, while the rest of us pray that modern medicine keeps the rest of the court breathing. He will get an infrastructure bill with some democratic support, and then he will tackle one of his big-league items, probably immigration. He will demand fealty and obedience from House Republicans, offend half of the caucus, lose a bunch of support, get mad and see the whole thing fall apart in a pretty spectacular fashion. His ACA-repeal efforts will be caught on the crossfire, with conservatives seizing anything remotely non-insane from the replace side as an act of treason.
By the end of 2017 his legislative agenda might have stalled, most of the republican House caucus is looking to behead Paul Ryan and he will likely be feuding with Rosario Dawson, the cast of Dawson’s Creek or some random brown person that said mean things about him. If the economy hits a pothole (and we are due to hit one at some point), the GOP will get to the 2018 midterms badly bruised, lose the Senate, and Trump will probably be dead in the water in the run up to 2020, the ones that are actually important for redistricting.
The Republican coalition was fragile before the election. It still is. We will likely see that taking a toll once they actually have to govern. A Trump presidency will undoubtedly do quite a bit of policy and non-policy damage, but the GOP is probably going to discover sooner than later than governing is much harder than what they remember.