This is a fraction of the actual population which would happily move to the US but is kept away by immigration controls. 11 million on a population of 330 million is 3%.
You think the whole population of Mex wants to "happily move" into gringolandia? Naive and arrogant at the same time.
I mean there are people from all around the world who would like to move to the U.S, I guess because their situations in their home countries suck enough to warrant it or some cases because they are personally ambitious and the U.S is seen as the place to realize that ambition. Many of them are not allowed to move though because of immigration controls.
Are you saying it's impossible to keep 3% of the people out?