That's the problem with a dogma.
It can only be right.
So anyone who disagrees must by definition be wrong.
His wrongness can only have 2 reasons: ignorance or evilness.
If he's ignorant, he must - for his own sake - be convinced of his wrongness.
Because it's a dogma, of course after it is explained to him, he will realize his wrongness.
If he doesn't, he must be evil.
Evilness must, of course, be fought, and because the dogma is right, there is no question that the end justifies the means in fighting evil.
Essentially, this is the concept of religion at its core - any religion. I think religions by definition cannot coexist, at least as far as Christians, Muslims and Hindus are concerned (not exactly sure about Buddhists). Pretending different is either smoke and mirrors or the idea of people who don't really feel strongly about their religion in the first place (which is, of course, a good thing).
Personally, I think religions are one of the biggest dangers to the survival of our species.