To compete with Mexican labor (if it comes at 10% of the American labor cost) one has to be at least 10 times more productive to keep earning American wages. It is not easy, but possible.
Or do well-paid skilled jobs like nursing, a job which is impossible to send overseas unless you send the patients with it.
Or one has to lower their cost of living to meet Mexico's - which is about as likely to happen as people spontaniously becoming 10X more productive. The human body is not a machine that can be tweaked beyond it's capacity.