A serious question/speculation: is Trump going to last a full term (or two terms)?
It's not a simple question but I'll take a shot.
Maybe one with an administration that is, from here on out, scandal-plagued and therefore legislatively impotent.
A second term would be difficult just because of his age. He's the oldest person elected (Reagan only became older in office). Older voters remember Reagan had early stage Alzheimer's when he left office. He was rarely seen in public again. And he's quite unpopular with independents and, increasingly, Republicans. Tough sell.
He'll have the heavy advantage of incumbency, and it's a big one. It should not be underestimated.
It just depends.
However, considering what happened in Alabama, it's more of an uphill battle.
This term:
1) If the House of Representatives flips to Democrat (which is expected) in 2018, impeachment is more likely (not conviction).
2) If Trump's base continues to erode, then impeachment is even more likely, possibly conviction. (It's not like Republicans like him. They just know his base will blindly follow wherever he 'leads'.) If it keeps shrinking, Republicans will cut him loose after midterms. Happily.
3) If the House and Senate flip Democrat, you might also see impeachment and more speculatively conviction. Some Republicans are needed for this, but after midterms it won't matter, insomuch as midterms will be a full repudiation of Trump by voters if both Houses of Congress flip. Republicans will be scrambling to distance themselves from the stain of Trump.
4) Mueller factor: On the one hand Mueller's investigation will take awhile if history is any example (I posted on historical examples-- on the Mueller thread maybe?), but he's moving quickly compared to previous investigations, and one should know he's only indicting as needed. It's very likely to have progressed much further than anyone suspects.
5) Trump v. Mueller: Trump is 'sneakily' having his surrogates attack Mueller. I don't worry about Mueller's team losing focus.
Trump would have to fire at least two people to get to Mueller. And that still won't end the investigation (it would probably open another one).
Next developments: My money is on Jared Kushner and/or a superseding indictment on Paul Manafort. Outside money on the lawyer Trump blamed for writing his Tweet as an attorney/client confidentiality breach and possibly White House aides implicated in obstruction of justice or conspiracy.
I think the lag in indictments is indicative of entering the inner circle, which in this case is literally family, like Trump Jr. So my guess is that Mueller keeps pushing on the edges and then swoops in all at once. With concurrent state level investigations to backstop abuse of pardon power. This is America baby ! :D
Remember Mueller's top criminal legal advisor has argued > 100 cases in front of the Supreme Court. There has never been a legal team of this caliber assembled for this purpose. It's truly amazing to look at the composition of the team and their track records. I digress...
Trump is toast. When he is toast is the question.
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So to answer your question, a lot depends on midterms because impeachment is a political process, as is subsequent conviction. It's unlikely that Trump will be charged of a crime (outside of the impeachment process) while in office. Afterwards...
The House is probably going to flip. Even if the Senate stays Republican, it's a thin majority, which is why they shoved that disgrace of a tax bill through.
If the Senate and House flip by wide margins even in states Trump won, it will mean Trump has no political capital and that people really hate him. So highly increased chance of impeachment and possibly conviction.
It's impossible to predict the pace of the Mueller investigation, but my guess is it will affect midterms a lot as it progresses. The basis of impeachment will come from Mueller. The rest is politics.
Bill Clinton survived impeachment, and as loathsome as he is, he's a lot more composed than Trump and a lot smarter. He didn't need everyone's approval so he had advisers actually tell him what he didn't want to hear but needed to know, and he had a law degree so he had a basis by which to be advised. Trump's own lawyer, Ty Cobb, has been telling Trump that the Mueller investigation is winding down. It's not. Not a chance. Every legal indication through the tea leaves of indictments contradicts that assertion.
There's real concern about how much Trump will unravel as shoes drop. Unfortunately for him, military people in civilian position might not be helpful to him. If they feel Trump has become mentally unstable and a real danger to the country, then they might invoke the 25th Amendment. He would really have to go off the deep end though. Pence would also have to believe he'll become potus and the optics are good.
If he's rendered incapacitated by stroke or heart attack, then the 25th will have to be invoked. This isn't a political stance. The guy is old, obese, doesn't exercise, and has an unhealthy diet. The VP would be a huge consideration next election if Trump runs.
I think it's a slim-to-none possibility that the 25th is invoked unless he has a major health event, because it's quite drastic.
Realistically, Trump's second and third years will be seriously hamstrung by the investigation no matter what the outcome of midterms. As more evidence of Russian influence on the election emerges, (see testimony from Google, Twitter and Facebook for examples), and indictments are issued, it's going to be grim and ugly.
So my prediction: one term, with no more major legislation passed. (Paul Ryan is dying to cut 'entitlements' to lower the deficit

, but that's the third rail.) No wall. No more big spending. Puerto Rico remains a shithole and the legal immigration to particularly Florida has the potential to change the political landscape. (Imagine how Trump will feel when someone tells him).
Trump will want to run again. It's up to Republicans to deal with it. It will be interesting and exhausting.
Ask me for any references.
