100 years of American intervention has helped, a great deal, to make them shitholes.
Pfffft! Countries are like neighborhoods, they are a reflection of the people who love in them. Shithole neighborhoods are shithole neighborhoods because they are filled with shithole people. Same thing with entire countries. One need only look at failed states like Haiti, Zimbabwe, Nicaraugua, El Salvador, etc, etc ...
The condition of Haiti today isn't because of something the French did when they ran the place. The condition of Zimbabwe today isn't because of something the "whites" did when they ran the place and Rhodesia had the highest GDP in all of Africa. And while I might agree that the Spanish and Portuguese who ran all of the failed states to our south were inept and stupid, the condition of those countries today have nothing to do with anything the Spanish or Portuguese did when they ran the places, nor with anything the United States has done since the US effectively kicked Spain and Portugal out of the Western Hemisphere.
Shitholes are made by the shitholes who live there.
... Do we want these shitholes coming here?