On a sunny Tuesday morning in September 2001, jihadists flew two hijacked 767s into two New York skyscrapers in the name of Allah.

Father Mychal Judge, the gay fire department chaplain, selflessly rushed into one of the burning buildings and became the day's first recorded casualty. On another hijacked flight, United 93, a group of passengers, including gay businessman Mark Bingham, sought heroically to take the aircraft back from its captors, resulting in a crash in Pennsylvania that spared the intended target, the Capitol building.

Bring up 9/11 today and the conversation will almost inevitably turn to Bush, Iraq, and related subjects. To the extent that it means we've forgotten the lesson of that day—and of the London, Madrid, and Bali bombings, the murders in Holland, and the Danish cartoon riots—this is tragic.

The lesson? That we're at war with jihadists (and millions of their supporters around the world) who wish devoutly to see Western liberties replaced by Koranic law. To acknowledge this reality is not to buy into some nefarious right-wing agenda; it's to recognize a clear and present threat to liberal democracy—a threat that gays, above all, should take seriously, because tolerance of people like us heads the long list of things about the West that drive orthodox Muslims nuts, and because we'd be among the very first to suffer in a society governed according to sharia.

No, the folks on the Christian right are no prize either. But they just reject their gay kids—they don't subject them to "honor killings." Even Fred ("God Hates Fags") Phelps doesn't encourage his followers to kill homosexuals, as innumerable imams have done. In Britain—where the Muslim population is growing apace in both size and political clout, and where at least two out of five Muslims, according to a Daily Telegraph poll, would like to see British democracy replaced by sharia (which would mean, among much else, hanging Elton John and Boy George in a public square)—formerly gay-friendly politicians like London mayor Ken Livingstone are increasingly turning against us to please them.

Such things can happen in the U.S., too. Indeed, examples of creeping sharia—for example, Muslim cab drivers who turn down blind people with guide dogs (because dogs are haram, or unclean)—can already be found in America.

To be sure, if you're young and gay in the greater Seattle area in 2007, all this can seem irrelevant to your daily existence. That's understandable. Never, and nowhere, has the simple fact of who you are been less controversial than it is in the very time and place in which you're lucky enough to find yourself. But don't ever assume (as many Jews did, for example, in 1930s Germany) that your comfort, security, and freedoms can't be taken away.

They can—in a flash.

So be aware. Be vigilant. Stand up for yourself, your way of life, your rights. Screw PC. And don't let anybody tell you that being concerned about other people's hatred of you makes you a bigot.

Bruce Bawer is the author of A Place at the Table: The Gay Individual in American Society (1993), Stealing Jesus: How Fundamentalism Betrays Christianity (1997), and While Europe Slept: How Radical Islam Is Destroying the West from Within (2006).