I think the world is better off without sacred cows, rather than with them. The only way to eliminate these kinds of reactions is via "exposure therapy". Admittedly, I say this as someone without many sacred cows. I'm non-religious, an anti-nationalist, and (other than a long career as a "non-denominational" anti-war activist) essentially apolitical.

I support the Mohammed drawing day, Koran-burning, and similar attempts involving other religions and political doctrines. When people do these things, it helps create a safe space for people to speak their reasoned criticisms.