Yesterday morning, the residents of London finally woke up to the jihad. Just as in New York, four years ago, and Madrid, in March 2004, London has now painfully met the enemy in our own land.

For the last four years, Britain has fought a “virtual” war-on-terror. Our engagement in the campaign has been total, yet – for most people – remote. Some complain of being “taken” to war in Iraq or Afghanistan, but for most Brits the effect of such conflicts has been negligible, affecting their daily lives not a jot.

And that fact has led to complacency – not from our superb intelligence or emergency services, but from the British public. Our press has been saturated with apologists and demagogues who claim that the war on terror is a fiction in the minds of George Bush and Tony Blair, or that it can be explained by a conspiracy theory (the theory for which changes most weeks). And, of course, there are those who complain that we are “alienating” or “upsetting” people by speaking in hostile language of division (as though they can blow us up, but we mustn’t even say anything hurtful). From Thursday, when multiple explosions rocked the morning rush hour in a trademark Islamic terror act, that discussion is finished. We must realize that this is not a public relations war, but war, period.

The choice we now face is whether Britain follows the example of America or Spain. Or, put another way, whether we go on the offensive and hunt down the terrorists, or retreat and hope they don’t hit us again. The timing of these attacks is clearly not (as in Madrid) intended to swing an electorate. At this stage, they appear callously designed simply to wound and kill British people while our security eyes were turned to the G-8 at Gleneagles, or perhaps remind us that just because you win an Olympic bid doesn’t mean you win a peace-dividend.

There are plenty of people in Britain who would like to go the way of Spain. They remain buoyed by the idea that if you get your troops out of Iraq, you can also get out of the way of the jihadists. They should be reminded of the scorecard. After Jose Zapatero’s appeasing socialist government was elected in Spain, and confirmed its plans to withdraw Spanish troops from Iraq, more bombs were planted on Spain’s railway system. Nobody did more to avoid conflict in Iraq than the French government, yet it was a French oil tanker that was attacked off Yemen. This Islamist terror is indiscriminate and global. It is also non-negotiable – there is no “opt-out.”

So what do we do? For us in Britain, the answer lies at home: Like America, our conduct in the vital job of draining the terrorist swamps of Iraq and Afghanistan is right, but our conduct at home is not. There are swamps here, too.

Yet already, within hours of the attacks on London, the shadow home secretary, David Davis, was claiming in the House of Commons that “the terrorism that walks the streets of London has no face.” Police Commander Brian Paddick told a televised news conference that “Islam and terrorism do not go together.” Really? Because they’re making a pretty good fist of looking like they do.

But this hits at the heart of the problem. If you aren’t willing to recognize the enemy, how on earth are you going to defeat it? If we had pretended during the years of IRA terrorism that we were not specifically searching for suspects of Irish background, then we could never have countered Irish republican terror. And if the authorities in Britain are not even willing to admit that it is Islamic extremists who are the threat to our society, then we might as well bulk-buy burkas and pretend we can sit this one out with the Spaniards.

But we can’t. There is no opt-out. The only way to stop more terrorists from walking onto London buses and blowing them up is to get the terrorists before they get us. On the international scene, that means removing and replacing the regimes that harbor, train, and support terrorists. This job is being done. But on the domestic scene it means winding up the groups and mosques that have made Britain the central Islamist-terror meeting point in the West. For too long we have afforded rights, which we have fought for generations to achieve, to people who do not believe in such rights and only use them to abuse us and our society. Like all of the West, the British are tolerant people, but we must no longer tolerate groups within our midst who preach hatred against us. It is that preaching and the acceptance of it that is directly responsible for the carnage now lying in the streets and squares of one of our most beautiful cities.

We have to wake up to the threat within our borders. Ignoring it any longer implies that the threat is so serious that there is nothing to be done. But there is something to be done, and we must do it. Because this is not the culmination or completion of the jihadist wars within the West. These are just sickening and hate-filled opening skirmishes.

Mr. Murray is a best-selling author and journalist based in London. His new book, “Neoconservatism: Why We Need It,” will be published by the Social Affairs Unit in London this September.