Big money has managed to keep AMLO from the presidency by selling the idea that keeping Mexico in line with the West's economic policies is on the best interest of the Mexican people. If that line goes away, USA is two years removed from having an hostile goverment on its borders.
That is also true, the USA may lose latin america to China if they keep pushing Mexico.
But don't think it will happen, money talks, and we have to remember that NAFTA is not only a more than half a trillion trade agreement, but it also helps American companies do business in Mexico and Canada, it helps investors move capital between the countries, it would be such a reboot for the region. Is just a question of who will give up first, Trump or Peña.