THE COLUMN that these bombings may seem to invite trips easily from the tongue. “No surrender,” it says. The enemy “can never be allowed to win”; no quarter must be given; barbarity must be met by resolve; we are not weakened but reinforced in our defiance of evil; we owe it to those who have died not to deviate from our chosen path.

From Shakespeare to Churchill to Kipling — from Rourke’s Drift to the Blitz to Port Stanley — politicians and poets have given us templates for this oratory, and every generation rewrites it. Winston Churchill mastered it when Hitler struck. Franklin D. Roosevelt rehearsed it after Pearl Harbor. John F. Kennedy hurled it at the enemies of liberty.

Margaret Thatcher repeated it from the rubble of the IRA bombing in Brighton. It formed the basis of the American and British response to the mailed fist of Soviet communism. In the face of provocation a ringing declaration never to falter proceeds direct from heart to lip.

But en route it may detour the brain. Simple defiance is always moving but it is not always wise. Our resolve never to submit to blackmailers and bullies has echoed eloquently and often through the chambers of legislatures or the columns of newspapers, but sometimes we did later change our minds, and sometimes we were right to.

That same defiance was Churchill’s first answer to the movement for Indian independence. It was the initial response of successive British prime ministers to the bloody terrorist outrages before the founding of new states in Israel, Cyprus, Kenya and Aden. That defiance and resolution was for a decade the answer the governments of France gave the merciless terrorist movement in Algeria.

It was France’s at first unswerving response to insurgency in South East Asia, and it became Washington’s reaction — at first — to the murderous Vietcong. White South Africa’s answer to the ANC terrorism was no different; and today it is Russia’s reply to separatists in Chechnya.

Some wars are wrong. Some wars are right but unwinnable. Some wars are right, winnable and best won by sheer guts and force of arms, with all guns blazing. These are the easy ones.

But there are others which are right and should be fought, but with the utmost subtlety and patience, and only on the most carefully chosen ground. The War on Terror is one of these.

We did not start that war. Apologists for Islamic fundamentalism need reminding of September 11 whenever they speak. But in choosing Iraqi soil as the ground on which to prosecute and intensify this war, George W. Bush and Tony Blair made a colossal miscalculation, and I think they know it. Thursday’s atrocities in London may have been among the unintended consequences of that blunder.

To close ranks now is natural. When a Cabinet and Prime Minister handle an awful episode with the poise and command they showed this week, our instinct is to ask no questions.

But one question must be asked. In the glow of pride at how well our post-incident preparations coped with the mayhem, dare we overlook our complete failure to stop the terrorists before they struck? The Government’s efforts have been to counter the threat through surveillance, through security measures and through public vigilance.

Either these efforts were incompetent, or terrorism cannot be countered in this way. Is there a third possibility?

There must have been a huge undercover operation to guard against those bombings. In the week of the G8 it is impossible to suppose the risk was overlooked. Government will have taken every feasible precaution. And what happened? We got no wind of how, where, when or by whom these bombs were to be placed. No culprit was caught or even noticed in the act. We failed to foil a single bomb. And we have not, as I write, identified the perpetrators.

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