"The floggings will continue until moral improves"

Sometimes they win demands even when the strike is illegal. The 2018 West Virginia teacher's strike turned into a wildcat (unauthorized) strike but that didn't stop them from winning a 5% pay raise. It does depend a lot on community support and sympathy.

https://en.m.wikipedia.org/wiki/2018_West_Virginia_teachers%...

Some states it's just illegal for teachers to strike at all, wildcat or not, or even to organize with unions.

A wildcat strike is always illegal in the US. Organizing a union isn't illegal in any state, it's about whether the union gets official recognition and official bargaining rights. My point was that it's possible to win even if you don't have those things.

In jail they won't come to work either. That sounds more like a scare tactic

It's less of a scare tactic and more of a way to punish and prevent teachers from organizing in the first place.