“ISIS-K has been a thorn in the Taliban’s side for years. Formally known as the Islamic State – Khorasan, it has existed since 2015, formed initially by the defection of disaffected members of various other jihadist groups in the region, including some former members of the Taliban. The group initially gathered thousands of followers and seized some small areas in the east and north of the country. In the years since then, the group has declined in size and stature due to relentless pressure from the United States, Afghan and Pakistani security forces, as well as the Taliban.
It has also been notoriously resilient. A U.S. special operator once told me he estimated that the U.S. had killed “five-thirds” of ISIS-K’s manpower over the course of several years. Since 2015, the group has lost four emirs to capture or death in operations conducted by U.S. and Afghan forces. Reports estimate that by 2019, 11,700 ISIS-K militants had been killed, 686 had been captured and 375 had surrendered.Over the course of 2020, ISIS-K attempted to rebuild its forces from these heavy losses. These efforts met with mixed results, in part due to tacit cooperation between the U.S. military and Taliban forces in efforts to dismantle the group. Today, ISIS-K is generally estimated to have a few thousand fighters at its disposal and is considered degraded but not defeated, though such estimates may need to be revised based on reports of thousands of ISIS-K prisoners having escaped from Afghan penal institutions in the wake of the Taliban’s takeover.
Its resilience stems from the high degree of its members’ motivation, its network of alliances with other jihadi groups that provide ISIS-K assistance and multiply its reach, its attraction to disaffected members of the Taliban and other militants (especially from Pakistan), and its ability to recruit individuals from outside the Afghanistan-Pakistan region, including from India. One of the group’s key assets is its ability to attract a steady stream of experienced leaders and fighters from other local groups who know the region and how to survive in it.
Prior to the beginning of the United States’ withdrawal from Afghanistan, there was general consensus that ISIS-K was a threat outside of Afghanistan’s borders as well, with intentions to launch attacks on the United States and other Western countries. The combined efforts of the U.S. and others over the past five years have left the group without the capability to do so. However, U.S. intelligence estimates earlier this year suggested that if counterterrorism pressure were removed, the group might reconstitute the ability to attack the United States directly within 18 to 36 months.”
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“ISIS-K is also a sworn enemy of the Taliban. The group sees the Taliban as a bunch of sell-outs, who have abandoned the higher calling of a global caliphate in pursuit of their own goal of ruling Afghanistan. Calling them (among other things) “filthy nationalists,” ISIS-K has consistently sought to denigrate the Taliban and seize the mantle of jihad from its amīr al-muʾminīn (“Leader of the Faithful”), Mullah Haibatullah Akhundzada.
For the Taliban, ISIS-K represents one of two immediate internal challenges to its writ as the new government of Afghanistan (the other being the National Resistance Front). For the U.S., the group’s rivalry with the Taliban presents both opportunities and challenges.”
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“According to the head of U.S. Central Command, General Kenneth McKenzie, the U.S. has been providing the Taliban sanitized intelligence on ISIS-K threats in Kabul since Aug. 14. Further, he gave credit to the Taliban for having taken action on that intelligence, saying “we believe that some attacks have been thwarted by them.” So one opportunity is to build on this relationship of counterterrorism cooperation, at least insofar as it applies to the common enemy of ISIS-K.
A significant challenge, however, is how far to take such cooperation given both the political and operational risks. For example, the reported provision by the U.S. to the Taliban of names of Americans and Afghans that the U.S. wanted to be let through Taliban checkpoints created political uproar at home, with critics claiming that such action amounted to putting those Afghans on a Taliban “kill list.” Another major challenge is the Taliban’s cooperative relationship with jihadist groups beyond ISIS-K. The most notable of these from a U.S. perspective is al-Qaeda, which retains a small presence in Afghanistan and close ties to the Taliban that neither group is likely to sever anytime soon.”
https://www.politico.com/news/magazine/2021/08/27/what-isis-k-means-for-afghanistan-507034