A strong emotional response to something is a good indicator that one of your beliefs needs to be examined or that it is no longer working for you. It can take you by surprise. Now the tricky part is to make yourself stop what you are doing so you can feel the emotion and figure out what is causing it.
It is much easier to just react in an unthinking way, spew some emotional stuff back, and go on your way knowing the other person (religion, country, ideology) was wrong.
Don’t just react! Pay attention to your part in the encounter and choose your response. Live; learn; grow; evolve.