The voluntary aspect was breached by GM coming back with a much lower production number and higher cost.
Promised 40,000. Then 6,000 and wants $1 Billion.
He had the hammer and he decided to use it.
GM wanted to price gouge. Trump was having none of that.
We don’t have the whole picture yet (if ever). Agreed: ‘war’ profiteering is bad & it’s important to act. There can also be no doubt that Trump will not continue these measures for a long time. However, a sizable fraction of the Democrat party would support such command & control measures long term. That should give you pause.