To the extent that Trump campaigns on anything except fear of the other, it is about bringing manufacturing jobs back to the Rust Belt. The GM layoff announcement obviously strikes at the very heart of that message, and could cost him critical swing votes in 2020.
Trump has predictably already complained about it, just as he frequently complains about the Fed. Will he think the base will be satisfied with mere words, or will he actually follow up with some stupid or illegal actions to punish GM for doing what it has to do?
To use Ross Douthat’s term, Trump has mostly been just a dictator on Twitter thus far, but that could change if he thinks it necessary. As the election approaches, the pressure to produce results will probably result in more extreme behavior. We’ll see.