I think you are confusing apples and oranges.
What I said was that “removal was one thing”. We can have a debate about what constitutes good reasons for removal, and what political process best accommodates a needed removal. We can talk about whether we have reached a level of existential crisis such that a political actor could go beyond the regular bounds of the legal system to accommodate an exceptional situation. I believe that back in 1868, a Representative or Senator could have rightly voted to impeach and convict President Johnson (that is, consistent with his oath to uphold the Constitution). But the country survived Johnson and the Reconstruction programme blossomed under Republican majorities and subsequently under President Grant. So maybe I am wrong about the impeachment of Johnson. We can talk about whether we face a crisis of similar magnitude under Trump.
But that debate (in my opinion) should not involve loose talk about concepts from the criminal law. Eg: “aid and comfort”. The only thing you’ll accomplish going down that road is to produce confusion in Congress, in the courts, and in the public mind. If you are lucky, it will start and end with mere confusion. If you are unlucky, such a strategy will yield speech crimes, speech monitors, and a speech police. The game is not worth the candle.
Presidents are citizens too. They are allowed to have views—even controversial ones—including ones about which the President’s opponents disagree. If you are going to argue that the President’s expressing otherwise lawful speech about policy is a reason for removal, then I might add that that position is not precisely in tune with what a great many Americans believe about their political and legal inheritance.
If your dispute with Trump and your call for his removal are based on policy (and his language about policy), rather than about discrete factual predicates amounting to legal violations, then you should eschew the language of the criminal law and push forward with debates (in this forum and elsewhere) about the prospective dangers you think Trump is creating or the harms he has already caused. But as I said, the country survived Johnson. To the extent that the argument against Trump is based on his saying stuff you think outrageous, I think the country will survive his talking big. I would also add that Trump has done little (as I see it) which substantially departs from his campaign statements—so a removal based on political disagreement about the expected consequences of policy is not going to be one with a strong democratic justification.
Technical point: It may be that deporting foreigners is not a criminal punishment, but exiling/banishing/deporting Americans who are in the country legally would seem to me to amount to a violation of a 14th Amendment liberty interest. This brings up an important cultural divide in America today (and not just in America, but across the Western world). Many of Trump’s supporters see the elites as being indifferent between their fellow citizens and foreigners. I ask you not to prove them correct.
Seth Barrett Tillman, My Post on CONLAWPROF: my response to a discussion about removing Trump from office, New Reform Club (July 17, 2018, 9:04 AM), https://reformclub.blogspot.com/2018/07/my-post-on-conlawprof-my-response-to.html.