THERE’S A familiar ritual each time an operation to thwart a putative terrorist incident dominates the news. After the public’s initial expressions of relief and shuddering contemplation of what might have been, a rising chorus of sceptics takes over, with a string of questions and hypotheses.

Was it really a serious terrorist plot, or only a bunch of misguided, alienated Muslim kids larking about with a chemistry set and a mobile phone? Sometimes, unfortunately, as with this summer’s ludicrously overplayed Miami “plot” to blow up buildings in Chicago, in which the plotters had got as far as purchasing some boots but not much else, overzealous authorities bring this sort of suspicion on themselves. But you can guarantee that every incident now, whatever the evidence, will be treated with such derisive doubt. If the police had got to the 9/11 hijackers or the 7/7 bombers in time, a sizeable chunk of respectable opinion would have dismissed them as idealistic young men with no real capacity or intent to cause harm.

The scepticism is then embellished by the conspiracy-as-diversion theory. How convenient, cluck the doubters, with rolled eyes and theatrical sarcasm, just as the Government’s got some new bonfire of civil liberties planned; or just as President Bush’s poll numbers are collapsing; or just as Israel is stepping up its ground attacks in southern Lebanon.

Then, of course, whether real or imaginary or government-authored, the cynics will say the plot inevitably has its roots in our own culpability. If we hadn’t invaded Iraq, if Tony Blair weren’t George Bush’s agent of oil-fuelled imperialism, if Israel weren’t killing innocents in Lebanon, this wouldn’t have happened.

It is a neatly comprehensive schema of cynicism. If the plot turns out to be a damp squib, or the police have made some ghastly error, the sceptics will triumphantly claim that it was deliberately overdone to scare us. If the plot is real, or God forbid, as with 9/11 or 7/7 it isn’t foiled in time, then they can switch seamlessly to the claim that we’ve only ourselves to blame.

In this internally pure worldview, the consistent theme is denial— denial of the reality of the mortal threat we face, denial of the reasons we face it. The villain for these people is not the jihadist, with his agenda of destroying our very way of life. It is, as it has always been, that malign continuum of institutions of our own authority that begins with the aggressive police officer and goes all the way up via the credulous media and craven officials to No 10 and the White House.

It’s too early to say with any confidence yet, but it looks as though yesterday’s plot to blow up US-bound aircraft from the UK was closer to the 9/11 tragedy than the Miami-Chicago farce. If the police and intelligence authorities have succeeded in foiling such a murderous plan, the correct response is one of immense gratitude to them, pride in our security institutions and continued vigilance against future plots.

But we should also remember that our continuing existence lies not just in inconvenient security measures and uncomfortably intrusive intelligence activities, but in a grand global strategy. Success requires, in addition to the tiresome banalities of long check-in queues and tighter limits on hand luggage, a commitment, whatever the costs, to eradicate the deep global political causes that threaten us.

And for this it just won’t do to claim it’s all about bad US foreign policy. It is repetitive but necessary to point out that we didn’t start this war when we invaded Iraq. The attacks on 9/11 were planned not only before we invaded, but during a time when the US was expending extraordinary effort to try to forge a lasting settlement between Israel and the Palestinians.

And if our actions have radicalised the jihadists we should remember that they are animated at least as much by our ridding Afghanistan of their spiritual brethren, the Taleban, as they are by whatever crimes the US may have committed in Baghdad.

The same applies to Israel and Lebanon. Not only is the current war the direct result of Hezbollah’s aggression, its deeper causes lie in the continued determination of Israel’s enemies, increasingly emboldened by Tehran, to liquidate the Jewish state.

Few can look at events in Iraq or Lebanon today with optimism, but it would be dangerous folly to assume, as some do, that the West should retreat, beating its breast and promising never to offend again.

Events such as yesterday’s near-miss should remind us that September 11, 2001, gave birth to a radical and dangerous new world. It required the US — an imperfect country to be sure, but the only one with the power and the will to defend the basic freedoms we too easily take for granted — with its allies to remake the international system. It provided a terrifying harbinger of much larger atrocities to come, when terrorists and their state supporters get hold of weapons with which they can kill millions, not thousands. This new enemy is not like old enemies. It is fundamentalist and suicidal and apocalyptic. The old system, rooted in a liberal philosophy that relied on patient diplomacy and made a virtue of being slow to respond to attacks, was unequal to this new challenge. The new system required rapid action to open up the Middle East, the festering root of all these threats to modernity.

I will grant you that the Iraq war has been characterised, in conception and execution, by blunder after blunder. And it is certainly possible that, in their failures there, the US and Britain have made the world more unstable, not less. But we should not, in our frustration, confuse the real enemies here. We should not mistake the unlooked-for dangers caused by blunders and arrogance in Washington for the targeted threats posed by nihilism and hatred in much of the Middle East, and in some of our own cities.

Yesterday provided us with yet another glimpse of the awful reality of our long war and associated miseries. We must be very careful not to ascribe their creation to our own errors.

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