Trump pulling out of Syria. Will Afghanistan be next?

Against the advice of many in his own administration, President Donald Trump is pulling US troops out of Syria. Could a withdrawal from Afghanistan be far behind?

Trump has said his instinct is to quit Afghanistan as a lost cause, but more recently he's suggested a willingness to stay in search of peace with the Taliban. However, the abruptness with which he turned the page on Syria raises questions about whether combat partners like Iraq and Afghanistan should feel confident that he will not pull the plug on them, too.

"If he's willing to walk away from Syria, I think we should be concerned about whether Afghanistan is next," Jennifer Cafarella, the director of intelligence planning at the Institute for the Study of War, said in an interview Wednesday.

The US has been at war in Afghanistan for 17 years and still has about 15,000 troops there helping government troops combat the Taliban. The approximately 5,000 US troops in Iraq are training and advising Iraqi security forces as they continue to fight Islamic State militants, a battle the US entered in 2014 after IS swept into Iraq from Syria.

Before other officials confirmed the withdrawal decision, Trump tweeted, "We have defeated ISIS in Syria, my only reason for being there during the Trump Presidency." The aspect of this that he did not address is whether the extremists or others will fill the security vacuum created by the US withdrawal to regroup and pose a new threat.

The administration said it intends to continue combatting Islamic State extremists globally and could return to Syria if necessary. Still, critics launched a barrage of questions about the implications of Trump's decision, including whether it opens the door for Turkish forces to attack the Syrian Kurds who had partnered with the US Kori Schake, deputy director-general of the International Institute for Strategic Studies, wrote on the website Wednesday that the Syria decision ought to unsettle every ally that relies on US security assurances.

"The governments of Iraq and Afghanistan ought to be very, very worried," she wrote. "For if Syria can be so lightly written off, the fight arbitrarily declared won, what is the argument for continuing to assist Iraq — where ISIS is even more defeated? And if Trump has so little interest in stabilizing security and assisting governance in Syria, how can Afghanistan have confidence that he won't make the same decision about them, when the fight there is costlier and progress less evident?"

These and other questions about the Trump decision and its broader implications were on the minds of many in Congress. Sen. Jack Reed, a Rhode Island Democrat, denounced what he called a betrayal of the Syrian Kurds.

"Now the President seems content to forsake their trust and abandon them to a potentially bloody conflict with Turkey," Reed said. "This decision also significantly increases the security risks to our key regional partners in Israel, Iraq and Jordan."

Trump has argued for a Syria withdrawal since he was a presidential candidate in 2016, and he has repeated his view several times since taking office. Still, the decision appeared to catch many in his administration by surprise; Pentagon officials offered no details on the timing or pace of the withdrawal, nor could they square it with numerous statements by Defense Secretary Jim Mattis about the importance of remaining in Syria to assure stability.