Every day the UK doesn’t honour its promise to the Afghans who have helped us leaves a stain

This is not a campaign by soft-hearted wet liberals, the Labour Party or lefty lawyers. As Rachel Hopkins, the shadow veterans minister, told The Independent: “Britain’s moral duty to assist Afghans is felt most fiercely by UK forces they served alongside.”

Those who have supported our campaign to grant asylum to the pilot who came here by small boat across the Channel, and to speed up the resettlement of thousands of other brave Afghans, include a wide range of former military top brass, but also senior Conservatives and an array of patriotic establishment figures.

Our debt to those Afghans who worked with our armed forces during the two decades of our direct involvement in that country ought not to be a matter of party politics. But if it were, as a matter of national honour it ought to find more support towards the patriotic, establishment end of the spectrum. Which is why the refusal of Rishi Sunak and Ben Wallace, the defence secretary, to engage with the case for urgent action is so inexplicable.

It is now two years since the fall of Kabul and still thousands of Afghans who look to the British government for their protection are in danger. Thousands who have already been approved for relocation languish in Afghanistan, sitting ducks for Taliban reprisals, or in hotels in Pakistan, waiting to be allowed into the UK. Thousands more are waiting for their application to be considered under the Afghan Relocations and Assistance Policy.

The processing of applications has been speeded up recently, which is commendable, but the resettling of those already accepted is still going incredibly slowly.

It seems as if Mr Sunak regards them as just another group of undeserving would-be immigrants, who must be fended off by the unwelcoming incompetence of a system “suffused with deterrence”, in the unlovely words of Robert Jenrick, the immigration minister.

Yet these brave people are not part of the normal immigration and asylum system. One of the welcome distinctions drawn by Boris Johnson as prime minister was to separate Ukrainians, Hongkongers and Afghans who worked with UK forces from the normal immigration channels. What is more, the total number of Afghans is relatively small, while the moral case is overwhelming.

As Lord Richards, the former chief of the defence staff, said to The Independent: “I and many others who had the privilege of serving in Afghanistan alongside our Afghan comrades have been very patient over the last two years, but the confusion and lack of action on the part of the government is now beyond the pale and they must resolve this.”

The government set itself a deadline of two years, which expires on Tuesday, and yet we estimate that around 18,000 individual applications still wait in limbo. This is no way for a country to discharge its obligations. It is shaming that the pilot for whom we have campaigned, who served with both British and US forces, is now looking to the United States to help him. And it is embarrassing that so many of his comrades, whose applications to be given refuge in the UK have already been accepted, still wait to be relocated.

As we have said before, the betrayal of “Operation Warm Welcome” has been damaging to Britain’s international leadership and reputation. The failure has been unnecessary, and it could be put right if the prime minister and the defence secretary had the political will.

Britain can still do the right thing, and the government need not worry about looking weak on migration, because the scheme commands such widespread public support – extending far beyond the usual suspects on the liberal left.

Winston Churchill and Margaret Thatcher would have done something about it. It needs action this day.