Koran burning is rude, but it's no excuse for violence

If you see a vicious-looking dog in the street, it's probably not a good idea to poke it with a stick. You'd be a jerk, and a fool.

If you see a vicious-looking man in a pub, it's probably not a good idea to insult his favourite football team. You'd be a jerk, and a fool. But unlike the dog, the man is culpable for his actions. If he reacts violently, it is he who should be condemned.

Nobody has a right not to be offended. And being offended does not confer a licence to behave as you please.

According to the BBC

Thousands of protesters have taken to the streets across Afghanistan over plans, now on hold, by a small Florida church to burn copies of the Koran.
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President Hamid Karzai said the burning plan insulted Islam while Indonesia's leader said it threatened world peace.
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Many of Friday's protests in Afghanistan were held after worshippers emerged from mosques, following Eid prayers marking the end of Ramadan.

Some demonstrators burned a US flag and chanted "Death to Christians".

Burn flags if you like (provided they are your own). Burn bibles, copies of the US Constitution, The God Delusion, and The Satanic Verses (provided they are your own). But "Death to Chrisitians" and "Behead those who insult Islam"? World leaders should dismiss Terry Jones as impolite, but their scorn should be directed at those who would take insults as an excuse for violence.