10 USC § 2808 gives the President authority to use the military to undertake construction in the event the President declares a national emergency. It has been used, without controversy, to build military facilities in Iraq and Afghanistan. 33 USC § 2293 is an even clearer grant of statutory authority to the President to order construction, "without regard to any other provision of law," in the event of a national emergency that "may require the use of the Armed Forces," where the construction is "essential to the national defense."
Securing our southern border is vastly more important to our national security than is nation-building in the Mideast. Indeed, it is vital to our national survival, as Pat Buchanan argues in a recent column.
There is little point in having a military if it can't be used to defend the physical borders of the United States. Ann Coulter has been arguing from the beginning of the Trump Administration that the President has the Constitutional authority to use the military to build a border wall. Trump listened to Coulter when he refused to agree to an appropriations measure to fund the government without funding for the Wall. Trump should listen to Coulter again.
It is not, as some Democrats claim, "immoral" to build a border wall, the only purpose of which is to deter illegal entry into the United States. If a wall is built, genuine asylum seekers could still seek asylum by going to any American embassy or consulate. But those seeking to enter the United States to bring in illegal drugs or to commit violent crimes on our soil or just to work in the United States when not legally authorized to do so wouldn't be able to. And the plan of some Democrats to secure lasting political power by effecting the demographic transformation of the United States would have been dealt a blow a later President could not undo with the stroke of a pen.
A border wall would be a lasting statement that it is Americans who decide who becomes an American. It would also be a lasting statement that Americans want their country to survive as one of the distinct nations of the world. Build the Wall, Mr. President. Salus populi suprema lex.