To whom it may concern:
Re this ongoing discussion of illegal immigration, largely though not exclusively from Mexico, the Mexican government, outside specific treaty obligations, are there any such, has no particular responsibility or duty regarding the enforcement of U.S. laws, immigration or otherwise, especially when the government here has not displayed any particular concern, as evidenced by action, real action dircted toward securing the borders of this country, from illegal immigration. If I'm missing a salient point of two, let me know.
Having said that, and at the risk of repeating myself, worse things than this can happen, this illegal immigration from Mexico toward and or to the U.S. serves, for the government of Mexico, as a most convenient SAFETY VALVE, without which the government of Mexico, whichever government or party happens to be in power, might have to make some real efforts in the direction of improving things for their population.
Given the fact that such action would cause some degree of economic discomfort and or inconvenience to "The Powers That Be" in Mexico, do not try holding your breath waiting for the government of Mexico to undertake such action. The only way that this situation might be mitigated is for the government of this country, whichever party might hold the reins at any given time, to take serious action directed at securing our borders. Of course, such action might well cause our own "Powers That Be", a degree of economic inconvenience or discomfort, so don't hold your breath waiting for that to happen here either.
No, I don't have an answer to questions posed by the above analysis, which could turn out to be dead wrong, I don't think it is, but I guess it could well be. However, unless or until both be governments quit lying and start to deal honestly with existing sitations, no resolution will be obtained.
This follows through all the way, from illegal immigration to and including drug smuggling, where it trns out that while the government, the police and others in Mexico might well be "on the take", similar considerations apply in the U.S., it is in the U.S. where drug peddlers find a large number of customers.