It was just a minor story on Friday about a Dutch politician being denied entry to Britain at a London airport. You might well have missed it. But it was an extremely important event for its broader meaning. Geert Wilders, a member of the Netherlands parliament, was invited to Britain by a member of the House ot Lords. The invitation asked Wilders to show his 17-minute film “Fitna,” which he made last year. Fitna juxtaposes quotes from the Koran with images of Islamofascists attacking and murdering various non-Muslims. Last year there were riots around the world by Muslims against this...