The NRA supports gun control and they will endorse Trump's decision to sign Nancy Pelosi's bill to create a Universal Background Check (which, in turn, requires National Gun Registration in order to enforce.) Trump is on record as being willing to sign legislation outlawing so - called assault weapons and he supports waiting periods.
When you study politics, it is like watching World Wrestling Entertainment. Trump looks like he kicked ass on that nutty wall idea, but he will cave on gun control (he proved that with the bump stock ban.)
Having built a government so big and intrusive that it cannot be resisted, the gun owners will cave and turn in or destroy their firearms by the millions. Most of them will realize that if they bury their weapons, it won't be worth a tinker's damn to them if they really need it. And, since the creation of the wall will also finance an army of federal machine gun toting mercenaries with eyes in the sky (armed drones) the sheeple will not dare stand firm for their Rights.
They will accept the Universal Background Check, followed by registration, then the criminalization of private party gun sales and then high capacity magazine bans, "evil" features and finally confiscation. The fix is in and the sheeple fell for it - hook, line, and sinker.