It's a competitive job market. Why are you talking only about Mexico? You probably forgot about the refineries? They will close as well. What to do? In addition to these places come the Japanese.In the end, not just jobs and capital leaving America.
Competitive job market is OK. I don't have any issues with Americans importing cars from Japan. The Japanese technology is one of the best and they pay their workers above average wages. On the other hand, the Mexicans are able to manufacture cheap cars, using slave labor. And in addition to that, the quality is not that good.
Not much jobs would be gone, but you would get more qualified labor, plus better industry. Some jobs are due to die, and they will when robots become cheaper then human. But someone gotta operate those robots, overlook them and repair.
Automation in 99% of the cases target unskilled labor. It is not very easy to replace highly skilled labor, even using Robots. Perhaps that is one of the reason why Nissan still uses a 100% manual process to manufacture car engines for its brand GT-R. After the engine is manufactured, Nissan places a nameplate of the engineer who built it, over the engine.
