This has been one of the most disturbing things during the Trump administration. After everything he has said about illegal immigration and national security being jeopardized at the southern border, the actual results have been pathetic -- disastrous. If his officials were undermining him, why did he not simply fire them all and hire the right people? Now the ICE officers have concluded that Mr. Trump is not really serious, and they have even presented their views publicly. And he has done absolutely nothing about the illegal sanctuary cities and states which have cropped up during his administration.
I believe that if Mr. Trump had been totally serious about the border wall, he would have (1) made a proper televised address to all Americans from the Oval Office at the start of his administration, and provided the facts and figures relating to this very serious problem (not random tweets), (2) he would have found the money for its construction out of the defense budget (and other wasteful projects), rather than going to Congress, and failing to veto bills which opposed him (3) he would have kept the construction details of the border wall a classified military secret, since it involved national security, (4) he would not have talked about "fences" or "partial walls" as though this whole thing was a joke, (5) he would have ensured that the border wall went 50 ft above grade and 50 ft below grade (after searching for and destroying all the tunnels along the border, (6) he would have placed the National Guard all long the border with serious intent (while it was being constructed), since he declared this a national emergency, and (7) he would have had drones patrolling that border 24/7, with warning leaflets dropped into Mexico and Central America, that illegals breaching the border would draw lethal fire from the drones. If necessary he could even have shut down the southern border temporarily to show his seriousness.
Since billions of dollars are still flowing to Afghanistan, Pakistan, Iraq, and Central America (and other hostile nations), all that money could have been shut off and diverted to the initial cost of the border wall, while the troops were brought home to beef up national security within the borders of the USA. Furthermore, when a trade deal was made with Mexico, the cost of the border wall and the issue of illegal immigration through Mexico should have all been part of the package. To the best of my knowledge, that was not the case. Thus all the expenditures for the wall would have been recovered from Mexico (which Trump publicly proclaimed at the start).