Mexico is overrun with endemic corruption and most of the people live in poverty as a result. I know it's unthinkable but the best thing that Mexico could do for it's people is join the United States as another state or two.
Doing so would quickly put an end to the corruption, and Mexico is rich with physical and locational resources that would provide wealth and employment opportunities for all the people who live there.
They have millions of acres of very desirable land that would quickly be built out into homes, hotels and businesses. The construction industries would boom, and as people moved there all the support businesses would also boom. Educations for the people living there would improve immediately, and industries would move there to take advantage of the better educated workers. Healthcare would also improve quickly.
Oh but that won't ever happen, their corrupt government officials who live like royalty at the people's expense like it the way it is, and the people in Mexico don't have what it takes to throw them out.