What constitutes a Hostile work place? When would you say enough is enough?

The ones that lead by fear rather than doing the right thing. The ones that have cliques, and if you aren't part of the clique you don't get anything. The ones that tell you what not to do, then do exactly that

I hate the ones where there is obvious discrimination. Where the leaders think the only way to communicate is to use fear to control, and where that doesn't work, resort to constant yelling and downgrading with many idle threats. It is not fun having someone tell you frequently how they are wanting to take your rank and tell you that you are useless. This happens even today in our military and its not ok.

The worst leaders I've seen in the military are the COLs trying to get their stars. They tend to push everyone to their limits so that they can get/take as much credit as possible. Beyond that, a lack of stability. Leaders who seem almost schizo - ie, you're the greatest soldier one day, and a complete dirt bag the next.