Kaus and Coulter are frustrated that Trump, who stood out by talking about some specific things that could be done to restrict immigration, has done virtually nothing in terms of congressional action, despite having majorities in both houses. Attorney General Jeff Sessions, who is often criticized by the President, has carried out some of the restrictionist agenda by executive action, as have other officials. (As for the criticism, I think Sessions made a mistake in recusing himself so completely and so quickly, and perhaps above all, without even consulting Trump who had given him his job. Sessions put his personal honour before other considerations). Kaus says that with the off-year elections coming, Trump has foolishly let his support among his core or base slip away.
The more common criticism of Trump is that he is too right-wing, likely to casually disregard laws and the Constitution,full of hate for people who shouldn't be spoken of this way, especially if they are women or visible minorities, etc. Kaus summarizes all this by saying Trump has offended, and will continue to lose, the Hillary suburbs.
Trump wants to take credit for being solely responsible for his successes. One can understand him thinking he has gotten as far as he has not only despite disregarding what the experts say, but precisely because he has been free from the expert group think. He is over 70, and he is only too likely to think that whatever has worked for him in the past will keep on working. There was a theory for some years that after his Atlantic City fiasco, he was unable to raise any money from U.S. banks. One suspects this was always an exaggeration, but in any case it was supposed to explain why he would take money from Russian oligarchs (cash only!), and then owe them favours, eagerly spy for Putin because Trump supposedly has no morals in the first place, etc. Then in connection with Anthony Kennedy's retirement from the Supreme Court, we hear an entirely different story. Kennedy's son Justin, who was working at Deutsche Bank (not a Russian oligarch, not beholden to Russian oligarchs or Putin) was happy to lend Trump tons of money. It probably didn't need to be in cash if that was somehow awkward. Then a new theory: Trump corruptly promised Kennedy senior that Trump would nominate someone he would approve of (a strict constructionist?); in return for all this money. One ad hoc theory awkwardly piled on another; the headline seems to be that there are no Russian oligarchs in this story. Also: Trump is good at getting money from banks. He's always been good at it. It never seems to be much of a struggle. So he keeps doing whatever he does. (Also later in his career there were cases, such as in Toronto, where investors got the impression that Trump was investing his own money--for marketing purposes, this helped to attract investment--but he was actually getting paid for licensing his name. How many people can make money like that?)
So: has Trump under-estimated the fact that he lost the popular vote (I would like an investigation of the California vote myself, but that's another matter), so that he now thinks he can't do any worse than he did in 2016, and if the economy is good, particularly with unemployment falling and wages rising, he's likely to do better? Does he think it's safe for him to threaten both his core and the Hillary suburbs, at the same time?
To some extent presidents are expected to be uniters rather than dividers. Trump in 2016 apparently wanted to be the anti-Obama,and he was no doubt more divisive than many of us would like him to be. We may all be living with the results of the catchy phrase "fake news." If we all learn to distrust all news,then ideologues who want only their own news to be available, may act accordingly. The owners of Twitter, etc. are much more likely to listen to progressives than anyone else, and the progressives probably think, or enjoy pretending to think, that Trump won partly because his nasty core supporters somehow won the new media, or the internet wars,even while Hillary was always complacently ahead with old media. The progressive new media were nastily anti-Bush Jr., they did some of Obama's dirty work for 8 years,they may never have been thrilled with Hillary, and they are not going away. Trump says on twitter that he enjoys meeting with Tim Cook, who is hiring a lot of Americans. How much of this does Trump understand? Does he have an actual strategy to deal with it?