Running out of ideas

I apologize for again bringing up another Republican Debate, but I find them fascinating. The difference in mindset between liberals and conservatives has become so stark, that I find myself baffled that we're actually able to co-exist in the same country - I suppose that is why the live in Texas and the midwest, and I live in Portland in the northwest.
Regardless, I couldn't help but be amazed at the fact that Republicans are still bringing up this Mexican border fence issue this election cycle. I certainly understand that illegal immigration is an issue that needs to be dealt with in this country; I think that both liberals and conservatives would agree, but our solutions to the problems are vastly different.
While almost every one of the Republican primary candidates support building a wall along the entire nearly 2,000 mile border between Mexico and the United States, at a cost of nearly $50 billion over 25 years, none of them seem to be bringing forth any real comprehensive immigration reform (short of calling them illegals and saying we should throw them out).
As I said before, illegal immigration is a problem. It is a problem, because it costs the country a lot of money, and greatly reduces the opportunities available to the immigrants themselves. However, simply trying to stop people from immigrating illegally into this country by building a wall is folly; it would be much more beneficial to face the reality of why so many people are immigrating to this country in the first place.

*Interest side note: illegal immigration has slowed dramatically due to the global, but more specifically the United States', economic crisis. The opportunties that once abounded for illegal immigrants are no longer as plentiful. Coupled with the fact that there are so many legal citizens in this country who are now willing to do work that they before were unwilling to do, and therefore because jobs for illegal immigrants.

The issue with illegal immigration - the main issue - that no one wants to speak about is the fact that the Mexican government is corrupt and the mexican economy is terrible. The United States has consistently over the course of the last century taken advantage of this close neighbor, never allowing them full sovereignty to determine their destiny in the world. We've time and again coerced them into signing treaties that benefitted the United States and Canada, to the detriment of Mexico. Surely it doesn't make any sense that the United States and Canada have had such robust economies, while Mexico's economy has rotted in the gutter. Their currency has remained fairly stable, despite a few hiccups here and there.
The problem is that NAFTA allows Mexico, Canada and the United States to trade tariff-free, giving the United States and Canada the ability to import cheap goods from their southern neighbor, but giving Mexico none of the benefits that tariffs give to companies who trade worldwide. Overall, the United States has used Mexico specifically for the use and benefit of the United States - to the detriment of Mexico - and then complains when Mexican people want to flee illegally into the United States to try and create a better life.