Actually this only increases tensions.
It's one thing to be a heathen... Christians feel sorry for them. Muslims and Jews think of them as outsiders...
But overall... us heathens are worshipping something else or nothing. It's our problem, right?

It's quite another thing to be a blasphemer or a heretic. Same God... but different rules?! That's troublesome.

Although looking at things realistically... the holy wars have never been about religious differences. It's about resources and political power. The religion label is only used as a good excuse to mobilize the masses and get people with no actual common ground to work together against people who wouldn't necessarily be all that bad to them.
Holymen are the rationalizers of war and oppression...

__________________
"Man lives in the sunlit world of that which he believes to be reality. But unseen by most is an underworld, a place that is just as real... but not as brightly lit... A DARK SIDE!"
-opening from Tales From the Darkside