Because its exactly what's inline with their idea of the America they want. A big point that Rightoids loved to crow about is all the evils of globohomo and the stranglehold it has on White America. They don't care about upsetting our allies, because their America shouldnt have allies; Having allies means you have obligations and cooperation, and those come at the cost of money and time that "should be spent domestically". They don't care about America backing out of any world organization, because their America shouldn't be involved with the world's issues. A problem in some far flung land doesn't concern them here. Unless its Greenland. Or protecting Israel.
Ultimately, their retarded desires are nothing more than Gulaghomo painted in the red, white, and blue, with them at the helm of it. Sure, They're also in the gulag, but that's just a mistake made by those dastardly boyars Senators and Congressmen, they'll be released when they tweet to the good and loving Czar President, whom would never let a true patriot suffer.