Because tolerance of intolerance is intolerance. I don't understand why you Republicans can't comprehend that. In other to be tolerant, you must be extremely intolerant of things that aren't tolerant.
Only if you have no belief whatsoever in the power of your own example and your own message. In that case, I suppose you would want to use some form of coercion.
But then, I question your true motives for believing what you believe. Is it to join the majority and avoid the shame and invective of being accused of intolerance? Or is it because you truly believe that tolerance is superior? If the latter, why not act like it's superior and let it stand on its own merits? Why not show everyone a shining, pure, hypocrisy-free example of what real tolerance is?
See, what many of you really want is is to issue righteous judgment against those who disagree with you. You think the fact that you are right excuses this desire. You still haven't performed the introspection and the difficult internal work of overcoming and transforming your own hatred. You think espousing the correct doctrine makes you superior, but you did not eliminate your own hatred at all. You merely found a socially acceptable way to channel it. This still fails to reduce the amount of hatred in the world. Hating evil does not make you good, no matter how desperately you want to feel self-righteous.
The failure to comprehend this is not because it is so difficult to understand. It's really simple, in fact. No, the failure to understand this is the same failing behind most of the vices that remain today: it raises too many difficult and uncomfortable questions concerning who you really are and why you believe what you believe. It's so much easier to find something external to yourself to hate. Isn't it?