If China offered the Southwest to Mexico the latter might be part of the same problem. IMHO, they are.
Sure. That's the real impetus for letting so many illegals in: here, they are productive and under our influence - send them home poor and unemployable and they are likely before long to become revolutionary soldiers under the influence of Chavez, Castro, and, from afar, China.
Latin America is already in play, and our betters have apparently determined that an open border is the best way to spread the influence of American capitalism and blunt the advance of socialism there.
And they are quite annoyed at us for focusing so much attention on the attendant societal disruptions of illegal immigration, for they consider those things short-term and irrelevant. ;)