I think diplomats should suggest to Mexico that they open their borders to any USA citizen who wants to go to Mexico and live forever, but allow them to retain USA citizenship, but vote in Mexican elections. Yhey can buy any property they wish, any business they wish, be eligible for any government program available to Mexican citizens, travel anywhere they wish. If they want to talk about fair, make it fair, not just one sided in Mexico's favor. Then all our retirees can buy property in Mexico and we can take over their economy as well. Mexico can be the 51st State as far as I'm concerned.
Maybe we need a few thousand Americans to walk across the border (not at a legal port of entry), squat some place, set up a tent city, and then dare them to make us leave.