Long ago I posted an article from the Smithsonian (now closed due to the government shutdown) regarding the difficulties in building the proposed border wall:
Now we see the ripple effects of President Trump demanding American taxpayers pay, via our own government budget, for the wall that he himself said some 20+ times would be paid for by Mexico (http://fortune.com/2018/12/13/trump-mexico-border-wall/). Those 800,000 federal workers on furlough or working without pay were not enough to have our President “get off the wall” (sorry, had to use the pun). Now we see the profits of big corporations negatively impacted by the government shutdown. Perhaps that will be enough.
Keeping Wall Promise Is Blocking Other Signature Trump Pledges