Opinion | We Still Haven’t Figured Out How to Beat ISIS

For all of the counterterrorism wins that the United States has had in its fight against the Islamic State — and there have been many — we still have not figured out how to defeat it.

A terrorist attack targeting a concert hall in the Russian capital of Moscow on March 22 killed more than 130 people and left many others severely wounded. It served as the latest deadly reminder that the Islamic State — and particularly its Khorasan branch, ISIS-K, which is active in Afghanistan, Iran and Pakistan — remains a potent threat. It’s a painful lesson Afghans and Americans alike learned in August 2021, when ISIS-K conducted a complex suicide operation that killed at least 170 Afghan civilians and 13 American service members in Kabul, in the midst of a chaotic U.S. withdrawal from Afghanistan.

Since the start of the new year, ISIS-K has launched lethal assaults in Iran and Turkey. Several ISIS-K plots in Europe have been disrupted, with arrests in Austria, France, Germany and the Netherlands. On Tuesday, four days after the Moscow attack, the ISIS-affiliated al-Battar Media published a message threatening Italy, France, Spain and Britain: “Who’s next?” Both France and Italy have since raised their terror threat levels.

All of these events point to what we now know: Stripping the Islamic State of its self-proclaimed caliphate is not the same as beating it. At its peak, the caliphate was as large as the territory of Britain, stretching from the Levant to Southeast Asia, and boasted over 40,000 foreign fighters from more than 80 countries. Forced from this redoubt, ISIS has reconstituted itself in other countries, going underground in less detectable — but more dangerous — forms.

To stop that threat from reaching America and its allies, the United States must prevent two decades of counterterrorism expertise from atrophying. There are other serious threats that deserve Washington’s attention, including Chinese adventurism and the challenge of artificial intelligence. But to keep Americans safe, counterterrorism must remain a strategic priority — and that includes finding a way to keep eyes on the Islamic State in parts of the world where we no longer have a footprint.

After the terrorist attacks by Al Qaeda of Sept. 11, 2001, the American public was told to brace itself, that the war on terror would be a generational one. The United States made some profound blunders in the decades-long fight that followed, and eventually, Washington turned its national security focus to different geopolitical threats. But neither of those facts obviated the need to remain committed to countering transnational terrorism. By pulling back troops and intelligence assets from active conflict zones, the United States has allowed groups like ISIS-K to rebound. It’s not the time to let up, or predictably, we will find ourselves facing a resurgent adversary.

The Islamic State is nothing if not resilient. Aggressive Western military campaigns helped dismantle the caliphate and have in recent years severely curtailed the operations of ISIS militants in other countries, including the Philippines and Syria. Rather than disappear, they have gone on to rebrand, enlist new fighters under the same banner and plot new attacks. Some have reappeared in other countries, better trained and harder to find and protect against. Some are intent on committing acts of terrorism like those we’re witnessing now, traveling across borders to infiltrate target countries.

How did a jihadist group operating from a remote region of Afghanistan manage to expand its networks and begin planning external operations with such global reach?

Part of the answer is that we left. Before the United States withdrew, ISIS-K was far more constrained, particularly its ability to launch external attacks. In a 2020 agreement between the United States and the Taliban signed in Doha, Qatar, the Taliban agreed to prevent terrorist groups from using Afghan soil to threaten the United States and its allies. In return, Washington agreed to fully withdraw its forces from the country. The stipulation to prevent terrorist groups from using Afghanistan as an operating base was primarily relevant to the Taliban’s longstanding, cozy relationship with Al Qaeda. The Taliban and ISIS-K, on the other hand, are mortal enemies and have been fighting each other since ISIS-K started operating in the country in 2015, at the apex of the Islamic State’s so-called caliphate.

So while the Taliban, once in power, may have intended to combat ISIS-K and keep its militants in check, its success has been mixed at best. Taliban fighters were highly effective insurgents but are proving to be far less effective in their still new counterinsurgent and counterterrorist role. They have made modest progress in eliminating ISIS-K commanders and reclaiming some territory from the group, but Islamic State militants still operate along Afghanistan’s borders — and still retain the capacity for spectacular attacks.

Precisely because the Taliban has enjoyed some success in limiting ISIS-K’s attacks within Afghanistan, the group has deliberately focused its energy on an “internationalization” agenda, including shifting resources to build a robust external attack network. ISIS-K now maintains a vast network of extremists it can tap into, spread across volatile regions such as the Caucasus and Central Asia. Thousands of Central Asians have joined the Islamic State, with many Uzbeks and Tajiks holding leadership positions, especially in ISIS-K. Militants from Central Asia now form the backbone of ISIS-K’s external operations cadre. “In the past year, the Afghan affiliate has planned 21 external plots or attacks in nine countries, compared to eight plots or attacks in the previous year and just three between 2018 and March 2022,” notes a report by the Washington Institute for Near East Policy.

Put simply: The Taliban is unable to contain the ISIS-K threat alone. The time has probably passed for trying to unseat the Taliban by discreetly supporting Afghan opposition groups like the Panjshiris of the National Resistance Front, who oppose Al Qaeda and the Taliban. Now it’s time for diplomacy. Washington and its allies could engage the Qataris or the Saudis to provide incentives for the Taliban to ramp up their pressure on ISIS-K, share intelligence and, perhaps in time, walk away from their past pledge to unconditionally support Al Qaeda and provide the group with safe haven. Maybe the Taliban has learned from Mullah Omar’s fateful refusal to hand Osama bin Laden over to the United States after the Sept. 11 attacks. Maybe not.

Either way, it’s unrealistic to expect the Taliban to be a reliable counterterrorism partner in an international effort to defeat ISIS-K. But some level of cooperation, however unappealing, is necessary. The human intelligence so critical in counterterrorism can only be gathered on the ground. With no American footprint left in the country, our counterterrorism interests would be better served with intelligence derived from Taliban security and intelligence operations directed against ISIS-K — a mutual enemy. The cooperation should remain limited to information sharing and should not extend to training or the provision of equipment.

Intelligence history is replete with examples of marriages of convenience between intelligence services for sharing threat information, even between adversarial countries. Although a “shadow war” has played out between Iran and the United States for decades, the United States still reportedly shared threat warnings on an impending terrorist attack with the Iranians in January. Washington did the same with Moscow two weeks before the ISIS-K attack on the concert hall.

Of course, coming to any kind of agreement with the Taliban is a deeply complicated and controversial endeavor. Even a highly restricted relationship with the Taliban would be distasteful and fraught with ethical dilemmas, given the regime’s human rights record.

But it’s been considered before. And the alternative is worse: a devastating attack directed at Americans overseas or at home.

Christopher P. Costa was a career intelligence officer and was the special assistant to the president and senior director for counterterrorism at the National Security Council from 2017 to 2018. Colin P. Clarke is the director of research at the Soufan Group, an intelligence and security consulting firm based in New York City.

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