Personally I really don't care. Marxists unions ruined Detroit. I rather see them fail and learn lesson than be propped up by a trade deal. Perhaps from those ashes a competitive auto manufacturer or two could emerge where unions do not exist.
There are lots of auto manufacturers in the South where unions do not exist.
Toyota has a major plant near Lexington, KY (Camry and Avalon) and a truck plant in Texas. They are building a huge new plant in Huntsville, AL.
BMW has a huge operation outside Greenville, SC.
Kia has a major car plant on I-85 in GA near the AL border. The Hyundai side of the business has a big plant in Montgomery, AL.
Mercedes has a big SUV plant outside Tuscaloosa, AL.
There are probably more, but you get the idea.
Elon Musk is moving his Tesla factory to Austin.