President Trump's abrupt withdrawal of American forces from northern Syria is forcing the Pentagon to acknowledge the possible revival of an Islamic State sanctuary that could be used to carry out attacks throughout the Middle East and West, reports Politico.

Between the lines: While the Department of Defense is considering options such as drone campaigns and commando raids, it would be difficult to trail and gain intelligence on ISIS members without troops on the ground, per Politico.

What they're saying:

Retired lieutenant general Michael Nagata told Politico, "Our goal was the defeat of the Islamic State, and they’re undefeated. Given how dramatically the strategic situation has now changed, the [U.S.-led] coalition may now have to recalibrate. Defeat has just become a much more difficult goal.”

Eric Robinson, an Army veteran formerly with the National Counterterrorism Center, said, "There’s a direct relationship between presence on the ground and understanding the potential danger. The unknown will be the capability and intent of the Islamic State in northeastern Syria to conduct external operations. Our ability to understand that has just been dramatically reduced," per Politico.

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