He's been pretty clear that he's only using "force" as necessary (3 or 4 times so far, I think). He's said most companies are happy and willing to help, so why "bully" them with it when you don't have to? That seemed like it was going to be the case with GM, but something obviously fell through there... so he used it.
I can't help but chuckle at the people in here that think, even in time of crisis, you can just snap a finger and make a shuttered car plant pump out ventilators. They've surely been prepping themselves for production while these discussions have gone on.
And before anyone replies, I know I know... if Trump had acted like a dictator in January he'd have a bunch of ventilators now. And you probably would've critiqued that as overstepping his bounds then and called for impeachment. I get the playbook, guys. You're not being as nuanced with all this as you think.