I am one who is quite willing to arrange “their own personal destruction.”
The only real point is how things evolve from here to the general election in 2020 and what support Trump, if re-elected, has for his agenda then. Anything he can do to get partial victory between now and then is fine, but the problems are not going to change drastically from now to the start of 2021, and he is trying to position himself to deal with them in the second term. Nothing will be ideal in this two year period with Democrats in charge of the House. But a lot will depend on who is offered up as their candidate in 2020. There’s a long game being played out. As for a wall, what you really want is effective border enforcement and that might take a multi-pronged approach. I never saw how a wall would work east of El Paso, and west of there, it’s probably best to have a combination of walls near strategic crossings, and electronic surveillance in long portions between them, beat the encroachers to the nearest road. This is how the Canadian border is managed. People think, oh you can just sneak across in the wilderness, and maybe you can but somebody knows it happened and is waiting on the logging road exit at some tiny town with a response. You can have effective national security without one continuous wall. The question is, how to guarantee effective law enforcement in a corrupt legal environment.
So many challenges for the president — but who else is there to face them? (I’m not eligible so don’t go there).