It doesn't strike me as much harder than drawing the line for more common reasons to fire someone, like incompetence or inappropriate workplace activity. Those

It doesn't strike me as much harder than drawing the line for more common reasons to fire someone, like incompetence or inappropriate workplace activity. Those are also continuums, and it's certainly not easy to know where to draw the line, and reasonable people will disagree about where to draw the line in each specific case. But we don't throw up our hands and say you can never be allowed to fire anyone for those reasons. It seems like many people think that "political" actions should enjoy a special protection and that no such actions should ever draw any criticism or consequences. The same attitude is common for actions labelled as "religious." I reject that special status.