WHEN YOU turned on the radio last Thursday morning was your first thought: “Phew! Great work by the security services”, or: “Here we go! Another stunt by the Government”? In other words, do you believe that the politicians were doing what most of us would put top of their list of duties: protecting the public? Or do you immediately suspect them of behaving like the fat boy in Pickwick Papers, whose catchphrase was: “I wants to make your flesh creep”?

Journalists such as Sir Simon Jenkins, formerly of these pages, belong to the latter group. He has written countless columns bemoaning the “climate of fear” and berating politicians and policemen for spreading panic by giving us warning of the terrorist threat or taking precautions against it. One classic of the Jenkins oeuvre, entitled “Nothing to fear but fear itself”, was published in The Spectator the very day that terrorists exploded 13 bombs on commuter trains in Madrid, killing 192 people and wounding more than 1,700.

Sir Simon, along with the many other journalists and readers who share his view, is in denial. There is a serious terrorist threat to Britain — and not just Britain. India, Indonesia and Iraq suffer from it as much as the UK, the US or Spain. These terrorists are not bogeymen summoned up by politicians to distract us from the scrapes that they get into, or to seduce us into giving them more draconian powers. If more powers are needed — and that is a question for another day — it is because the threat is real.

And just because the police sometimes make mistakes, as they did over the identification of Jean Charles de Menezes, does not mean that there are no other people wanting to blow up the Tube. They simply — and disastrously — got the wrong man. But they have got the right men too. Some 14 terrorist plots have been foiled since 9/11, and I have not heard the sceptics give the security services much credit for that.

These are not the only people in denial, though. Many in the Muslim community are too. Rather than face up to the fact that there are now worryingly high numbers of radicalised young Muslims, some of whom have murderous designs against their compatriots, these Muslims would prefer to delude themselves that the whole thing is a Western plot. A staggering 45 per cent of British Muslims, according to a poll by Channel 4, believe that 9/11 was a conspiracy between the US and Israel.

How could they, in the face of such overwhelming evidence? We know who the hijackers were, and they weren’t CIA or Mossad agents. They were angry young Muslims. If the US Defence Secretary Donald Rumsfeld knew of the attack that was about to happen, what was he doing sitting in the Pentagon, which was hit by one of the aircraft? If Israelis were in on the plot, why didn't they tell Daniel Lewin, a former Israeli commando, who struggled with Mohammed Atta and other hijackers aboard American Airlines Flight 11, the first plane to crash into the towers?

No, it is as preposterous to deny that Islamist terrorists undertook the 9/11 and 7/7 attacks as it is to deny that the threat of similar attacks in the future exists. But it is equally preposterous to deny, as Tony Blair and George Bush still do, that these attacks have nothing whatsoever to do with their foreign policy.

Of course, 9/11 took place before the wars in Afghanistan and Iraq. But the grievance still arose from US foreign policy, specifically the siting of American troops on Saudi soil. The subsequent two wars, and now the US and UK support for Israel’s actions in Lebanon, have only served to exacerbate that grievance. They hand explosive ammunition to radicalisers.

To say this is not to argue that the Americans should not have bases in Saudi Arabia, that they should not have gone to war in Afghanistan or Iraq, or that they should not have supported Israel’s attacks on the Lebanon. It is an entirely value-free observation. Whether or not Mr Bush and Mr Blair have been right in their judgments, it seems wilfully blind to deny that these foreign policy choices have had an effect on Muslim opinion. Even MI5 agrees. This comes from its analysis of the threat to the UK of international terrorism: “In recent years, Iraq has become a dominant issue for a range of extremist groups and individuals in the UK and Europe.”

Nor is it to argue that the US and the UK should form their foreign policy on the basis of the effect it will have on Muslim opinion. Mr Blair and Mr Bush may still be doing the right thing, even taking account of their policy’s inflammatory effect. But, having decided how to act, the two governments cannot then simply deny that there is any effect at all.

To observe that our foreign policy has angered Muslims is not in any way to excuse terrorism. If Muslims do not approve of Britain going to war with Iraq, they are free to vote Liberal Democrat or Respect, as many of them did at the last election. If public opinion swings strongly enough against British support for American foreign policy, it is quite possible that Gordon Brown or David Cameron will follow suit. The great virtue of a democracy is that you don't have to blow up trains or planes to make change happen.

These terrorists are not rational beings, though. They harbour a fantasy of Western democracies being intimidated into joining the Muslim world and living under Sharia. But they are not the only fantasists. There are far too many seemingly rational people — from Mr Blair to Sir Simon via a large swath of the Muslim community — who need to get real too.

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