(Just my little notes to some local people)
Mexico is the third largest trading partner of the U.S. Our exports of natural gas to Mexico have grown enormously, as their economy grows. And their middle class!
In 2010, pipeline exports of natural gas to Mexico, in million cubic feet: 333,251. In 2015: 1,054,271. Source.
Extra reading.
That of course, helps the state economies of Texas and Oklahoma. But if pressured or insulted or hindered enough, Mexico, as well as everyone, has an option. In 2016, installations of solar powered energy production hit a record, surpassing all other energy production (new additions). Extra reading.
And solar has already reached grid parity in Mexico.

Fossil fuels are going to be phased out, but how rapidly? Very rapidly (for us), if Trump keeps insulting peoples and nations and negotiating amateurishly.