In my experience (on the employer side), you will terminated for performance, terminated at will, or at worst terminated for insubordination, but not terminated "for cause". Terminated for cause is very serious and generally means a serious breach of some sort: embezzlement, harassment, breach of contract, etc.
Termination of any of the other sorts is much less serious, usually results in severance and unemployment eligibility, and if you're coming from a place that mistreats its workers, it's generally not a hard story to sell that you stood up for yourself and got whacked for it. Other employers know the jackass employers by reputation, at least in the local area.