The Trump administration has been lauding the seizure of virtually all of the previously held territory of the ISIS "caliphate" — the remnants of which are now holed up in a single town in Syria, fighting a fierce street-by-street battle to the death. The administration cites it as evidence of the functional demise of ISIS as an entity, although some experts have disputed this, pointing to a diaspora of thousands of fighters who have dispersed, choosing instead to flee and fight another day.
As the administration winds down military involvement in Syria, most of which has involved U.S. special operations forces working with allies, predominantly the Kurdish Free Syrian Army forces, an issue has arisen with the potential to adversely affect U.S. homeland security: We have been the Kurds' main supporters in the area, and they have reason to be concerned over the pullback of U.S. forces, which leaves a vacuum into which Iran, Turkey, or Syria might attempt to enter, given that all three are hostile to Kurds, Syrian or otherwise, and might seek to annihilate them as the chance offers.
The Kurds, confronting the possibility of a war for their very survival, and wondering about the reliability of continued U.S. support, have made clear that they cannot and will not be in a position to maintain custody of roughly 800 ISIS "foreign fighters" captured on the battlefields of Syria, whom they have held in prisons on behalf of the United States.
There is valid reason to be concerned over the Kurds' capacities to hold these individuals in the long term, and clearly something must be done, but this has put the United States in a tricky position: Exactly what should be done with these battle-hardened and highly dangerous terrorists who come from all over the globe, including various Arabic and European countries?
Recently, the White House has started pressing the Europeans to accept transfer of and responsibility for the ISIS fighters who hold European nationality and the Europeans, for their part, are resisting the demand (see here and here). Similarly, the administration has floated the idea of detaining ISIS foreign fighters in prison in Iraq.
Is either idea wise? There are cogent reasons to think not. Iraq's frequent prison breaks specifically designed to free terrorist detainees suggest the country's security forces are not up to the task (see here, here, and here).
And handing ISIS fighters back to their countries of nationality only works if the legal systems of those countries are competent to handle such individuals with a view toward incarceration. That isn't necessarily the case. Questions would inevitably arise as to the sufficiency of evidence — if any — other than having been captured on a foreign field of battle. And let's be frank: Many European countries are lenient even when handing out sentences for individuals convicted of acts of terror on their soil (see here and here).
During the Obama years, other models were attempted in regard to terrorist detainees at Guantanamo, which Barack Obama tried and failed to close. Obama's Defense Department farmed out terrorists to cooperating third countries like Uruguay based on assurances that they would be carefully monitored. Of course, this didn't happen, and many of them simply disappeared, some to be recaptured or killed back in war zones once again plying their trade as jihadists. (Donald Trump has neither expanded nor reduced the number of terrorist detainees interned at Guantanamo, leaving it in stasis with a significantly reduced population of about 40 of the most hard-core jihadists.)
Another model was to hand these individuals over to countries like Saudi Arabia, which placed them with great fanfare into reintegration centers designed to help them shed their extremist beliefs, later proclaiming the centers to be astoundingly successful. However, more than one dissident, as well as some academics, have questioned the official line and suggested that the centers are shrouded in such secrecy that it is impossible to objectively assess their success, particularly inasmuch as the kingdom has invested the program with so much money and hype that it might not admit to program failures.
What's clear is this: Any program involving handover of ISIS foreign fighters that risks in any way them being released, or permitted through negligence to disappear, subjects the United States to great risk. While there is little chance that any of them would ever manage to enter our country either through procuring a visa or through the Visa Waiver Program (for European nationals), nothing at all stops them from obtaining fraudulent or altered documents that might very well pass scrutiny at a U.S. port of entry. Even more concerning is the threat of simply crossing into the United States through our porous southern border. My colleague Todd Bensman has written extensively on this subject (see, e.g., here, here, and here).
What does that leave us? Once again opening up the gates of Guantanamo and holding those foreign fighters there. Messy and morally complex as it is, it may be the best of all the bad-to-worse alternatives (see here and here). Several senators have already suggested as much.
Doing so would be an extraordinarily expensive proposition. But in the end, which is cheaper: internment at Gitmo, or the risk of a mass terror attack on American soil by seasoned and brutal ISIS foreign fighters who get placed into the hands of a country that may not care where they go or what they do, once received?