Too much money and too much corruption would be curtailed with a wall. Open borders globalists have deep pockets; they also exist within Congress.
I still find fault with Trump for not making this attempt to build a wall in the first year of his presidency. Waiting till the majority in the House was lost and before the new Congress was sworn in raises definite question and concern and even his sincerity of wanting a wall.
What I am certain of, is he doesn't want to leave his post with having failed on building a wall; THAT is not in his character.
I am still not confident that he will seek re-election and certainly the DEMS could take the oval office in 2020.
Trump, and everyone else, had to deal with the realities presented.
I am sure that you realize that the House leadership structure and the version of the rules that they adopt (regardless of which party holds the majority and the Speakership) is carefully controlled to ensure that legislation will only come to the House floor for a vote that is
approved by the leadership. (The same holds true in the Senate, though the mechanics differ.)
The only bills that would come to the floor for a full House vote were those that Ryan approved and supported in advance.
Trump had to face reality when he was sworn in, Ryan was the House Speaker and McConnell was Senate Majority Leader. Those facts weren't going to change.
I suspect that he had to make some "deals" early on to get
some of his goals moved forward. Without knowing the details of this deal-making, all that we can do is guess and speculate.
It appears that he was able to gain their support for three main items in the 115th Congress:
1. Senate confirmation of justices and judges.
2. Mild version of tax reform (with the emphasis on the corporate side)
3. Funding to re-build the military (that was left in tatters by the prior administration).
Funding for the wall was clearly
not part of these negotiations (which is why we saw it only emerge at this juncture, as the 115th congress closed).
Regardless of the campaign rhetoric, every President must deal with the realities of the legislative leadership that is present.