Even after that attack, there was a reluctance to see the jihadist networks as a two-way street — that what they had once exported, could be imported. The official British government report — while acknowledging that two of the 7/7 killers had “visited Pakistan with their families” and at least one of them was “believed to have had some relevant training in a remote part of Pakistan” — said it could find “no firm evidence” of Al-Qaeda’s role. Al-Qaeda provided that evidence weeks later.

Since the ISI ecosystem is largely responsible for the radicalism problem in Britain and was behind one of one of the worst attacks in British history, one might expect Britain to be at the forefront of efforts to punish Pakistan for its relentless sponsorship of terrorism. Such expectations would be wrong. Britain’s official outlook on Pakistan, reflected by the BBC, is very sympathetic for two primary reasons.

The first is political. As the 7/7 report noted, the Pakistan trips the killers made raised no red flags at the time because “[e]xtended visits to Pakistan by young men are not unusual”: nearly half a million U.K. residents went to Pakistan in 2004 for “an average length of 41 days”. This is one metric of the intimate relations between the British-Pakistani populations and Pakistan. As Azhar showed, this is not just familial, but politico-religious.

The million-plus British-Pakistanis are a relatively small part of the overall population (about 2%), but they concentrate in wards of cities like Birmingham and Bradford. At election times, they form a key swing constituency, and some of the most influential figures that set the political agenda for the community are pro-ISI. The ISI makes life difficult for British-Pakistanis who oppose the Pakistan Army’s programme and this marginalisation means that, when courting votes, both political parties are wary of adopting anti-ISI positions. There is the added factor that damaging relations with the Pakistani diaspora would have knock-on effects for any party’s relations with the wider Muslim community.

The second, very much related reason, is security. The scale of the intermingling between the two populations provides obvious opportunities for terrorist planners. This was bad enough when NATO had troops and a friendly government in Afghanistan, as 7/7 showed. The Taliban takeover has blinded Western intelligence. It will now be much easier for Westerners to land in Pakistan, link up with terrorists in Afghanistan to receive training and orders, and return home without the knowledge of Western governments; it is not as if the Taliban will be stamping passports. The ISI will be there to offer itself as the answer to this conundrum — for a price.

It might seem absurd that Pakistan can be paid to neutralise some of the terrorists it produces or provides haven to, but the country continues to take advantage of it. Pakistan’s rent-seeking strategy is based on creating problems the West perceives as too difficult to confront, then demanding payment to mitigate the effects. 

For twenty years, Pakistan has been one of the largest recipients of British aid money, partly for counter-terrorism cooperation, and received even larger sums from the US. This money ended up helping the ISI support the terrorists it was supposed to be fighting, who killed thousands of British and NATO troops and tens of thousands of civilians in Afghanistan.

Incredibly, Pakistan never incurred sanctions or even lost its “Major Non-NATO Ally” status for installing terrorists in power in Afghanistan. With the Taliban restored to power, the terrorist threat to Britain is now, as Ken McCallum warned, indeed a “real and enduring thing”.