IN THE shade of the presidential palace in Kabul, in the furnace heat of Helmand, and on the flight from Oxfordshire, shouting above the roar of the Royal Air Force plane’s engines, the British pressmen who travelled to Afghanistan with David Cameron last week had really only one question: “Was it worth it?”

Was Britain’s 13-year military intervention in Afghanistan, whose imminent end the prime minister had come to mark on his 13th and probably last visit to the country, worth the £40 billion ($65 billion), 453 British lives and thousands of limbs it had cost? And if so, Bagehot privately wondered, why were they all wearing body armour, including blast-resistant underpants, as the plane came in to land? Why had Kabul suffered four suicide-bomb attacks that week? Why was the Afghan capital considered so dangerous by the Foreign Office that it would not let your columnist leave Mr Cameron’s entourage to spend a few days seeing for himself the progress its diplomats describe?

Mr Cameron’s answer was typical of the muddle British politicians have made of Afghanistan. Yes, it was worth it, he said, because there had been no repeat of the 9/11 atrocities, which were planned in Afghanistan. But if that constitutes success, why are British troops leaving? Despite the recent progress of the Afghan security forces—over a hundred of whom are being killed by the Taliban every week—no one, including the country’s newly elected president, Ashraf Ghani, is confident they can withstand the onslaught. And why did Mr Cameron rule out, even in extremis, British troops returning to the fray? Moreover, why, in his address to British troops, did the prime minister suggest the withdrawal, which he had promised in 2010, was in itself a mark of success?

Haphazard, ill-conceived and waged—often with great heroism—on a shifting prospectus, Britain’s fourth Afghan war recalls the old gibe that its foreign policy is the same as America’s, only a bit less. Yet even that may be out of date, as Britain’s recent reluctance to fight against Islamic State suggests. If so, the Taliban will have won a great victory. They will have bled the last vestiges of Britain’s claim to global power status into Helmand’s sand.

To understand how this has happened, it is important to appreciate how unsuccessful much of the British effort has been. It is not really true, as Mr Cameron says, that it started in 2001, when Tony Blair made his moving pledge to Afghans: “This time, we will not walk away.” For the next five years, Britain did little. It took the lead in an almost comically hapless effort to eradicate opium cultivation. An artistic British spy, and chum of Bagehot’s, was given the task of designing a propaganda poster, depicting an opium poppy, to be pasted around southern Afghanistan. By the time it came back from the printer’s, the poppy had unfortunately morphed into a rose. The poster was distributed anyway. In those years, Britain’s main military contribution consisted of a hundred Nepali Gurkhas, who were said to have a special way with Afghans, being Asian themselves.

Vast, remote, never-much-ruled southern Helmand was then overseen by a couple of hundred American special forces. They knew that, while Western policy was going nowhere, Afghanistan was changing: “They’re watching us, deciding which way to jump,” one of them told your columnist. By 2006, with the Taliban resurgent across the south, they had decided—whereupon 3,000 British troops were deployed to Helmand. With orders to end the warlordism on which Afghanistan’s problems had been blamed, they set about remaking the province’s government. This sparked a firestorm, which would at one point see 32,000 British and American troops deployed to Helmand, and which, even now that most of the foreign troops have left, still burns.

What lessons can be drawn from this disaster? One is to remember those of history. Afghans never forgot that Helmand was the scene of one of Britain’s imperial calamities, the 1880 Battle of Maiwand—indeed, during the 1980s, British and American spies kept reminding them of it, to stiffen their resolve against the Soviet invader. Another lesson is that, when trying to win the support of suspicious foreigners, it is best to keep your promises. Mr Blair, for whom history started with his own election to power, did not. The result was that, if there was a chance in 2001 of preventing the insurgency, by 2006 there was none.

That suggests a third, more difficult lesson, which is to promise only what can be delivered. Mr Cameron’s decision to set the end of 2014 as a deadline for withdrawal was, in part, an acknowledgment of this. His generals protested, arguing that, with a bit more time, victory was still possible. He did not believe them, and little that has followed suggests he was wrong.

Talking a great game

But that does not let Mr Cameron off the hook. The bungling in Afghanistan demanded, at the least, a serious reconsideration of the nature and limits of Britain’s diminished, but still considerable, power. The prime minister shows no interest in that. In his foreign-policy pronouncements he sounds almost as Messianic as Mr Blair. In Helmand, where his enraptured Labour predecessor said the “future of world security” would be decided, Mr Cameron reiterated his belief that battling jihadism was the “struggle of our generation”. Yet he has committed few resources to it—just half a dozen planes over Iraq, none over Syria and, soon, only a few dozen army trainers in Afghanistan. It is an extraordinary mismatch, between too much talk and too little action, in which it is tempting to see a fatal decline in British resolve.

That is bad news for Afghans, who perhaps needed fewer British troops than they had, and may now need more than they can have. Because the honest answer to the question demanded of Mr Cameron in Kabul is that it is too soon to say. If Afghanistan’s feeble state, built at such a terrible cost, is still standing a decade from now, the Western campaign will be adjudged profligate, brutal at times, but a success. If not, it will have been a fiasco.