President Donald Trump has ordered the complete withdrawal of all American troops from Syria within 60 to 100 days — ending the small US presence in the war-torn country, curbing the fight against ISIS, and weakening America’s ability to counter Iran.

Other reports say Trump is only considering taking troops out of the country and hasn’t yet made a final decision. When asked to clarify, the Pentagon said in a statement Wednesday morning only that “at this time, we continue to work by, with and through our partners in the region.”

Yet just one minute later, the president tweeted: “We have defeated ISIS in Syria, my only reason for being there during the Trump Presidency.” Sarah Sanders, the White House press secretary, added more than an hour later that the US “has defeated the territorial caliphate” and that America has “started returning United States troops home.”

Between the DOD and White House statements, it definitely seems more likely that the US will withdraw troops soon.

If that does happen, it’d be a shocking and sudden development — one surely opposed by the Pentagon — but not entirely unexpected.

There are roughly 2,000 US troops in Syria there to help defeat ISIS, mostly by training Kurdish fighters. However, Trump has long questioned American troops’ presence in the country.

In April, he explicitly said he wanted to bring all American armed forces in Syria home. But surprisingly, he changed his mind five months later, agreeing to keep US troops in the Middle Eastern country indefinitely. Now it seems he’s reverted to his original stance.

Why Trump may want US troops out of Syria

There are likely two main reasons Trump wants to remove troops now.

First, it’s what he tweeted: ISIS in Syria is defeated — well, sort of. The terrorist group has lost the vast majority of its territory in Syria (and Iraq) under Trump, mainly because of the US military’s thousands of airstrikes and the ground fighting by US allies on the ground.

However, the Pentagon still says that ISIS has as many as 17,100 fighters in Syria, and about 30,000 total between Syria and Iraq. That’s about how many militants the group had at its peak strength in 2014.

Which means that while ISIS is certainly far weaker as an organization than it was at its height, it’s still a long way from being truly “defeated.”

And that’s precisely what US military officials and many experts are worried about: the possibility that the withdrawal of America’s troops will make it easier for ISIS to regain territory.

Recall that in 2016, Trump repeatedly slammed President Barack Obama for being the “founder of ISIS” because he withdrew US troops from Iraq. Now that Trump is actually the one having to make the tough decisions, though, it seems his calculation is much closer to Obama’s than he might have expected.

The second likely reason for Trump’s decision to pull out now is that Turkey is planning a military offensive against the US-backed Kurds in Syria. Turkey considers Kurdish fighters near its border to be a serious terrorist threat and has vowed to remove them.

Turkey’s goal is to establish a “safe zone” between Kurdish-controlled territory and the Turkish border. Ankara has been fighting a decades-long insurgency against Kurdish separatists inside its own country, and thus considers the powerful Kurdish forces near its border to be a looming problem. There are genuine concerns, including from Sen. Marco Rubio (R-FL), that Turkey’s fight against Kurds in Syria could turn into a broader war.

The assault could put US troops in harm’s way, especially if they defend their Kurdish allies — who have helped defeat ISIS throughout Syria — from a Turkish assault.

Instead of dealing with that dilemma, Trump may have thought it best to get out now before the situation worsens.

That will surely sour relations between the US and its Kurdish partners. But the US may have signaled this move on December 17, when America’s special envoy for Syria James Jeffrey told the Atlantic Council think tank that “we do not have permanent relationships with substate entities. That is not the policy of this administration and has not been the policy of other administrations.”

So in a sense, Trump’s withdrawal move — if it happens — is somewhat defensible. Some experts, though, aren’t as sure.

“The US military’s mission in Syria has grown fuzzy and convoluted, and requires reassessment,” Mara Karlin, who spent years on Middle East security issues at the Pentagon, told me. “But unilaterally ending it — particularly absent meaningful coordination with our allies — is foolhardy.”

And the decision may be foolhardy for another reason: It hurts Trump’s own policy to push back against Iran.

A withdrawal won’t help Trump’s anti-Iran policy

For months, the Trump administration has said one of its main goals in Syria is to forcibly remove Iran from the battlefield. Iran cares deeply about Syria’s fate and has been funding and arming proxies in support of Syrian President Bashar al-Assad’s regime for years.

It was always unlikely the US would succeed in that endeavor. After all, the US only has 2,000 troops in the country, and they’re there to defeat ISIS, not fight Iran.

But the removal of US troops makes any success against Iran in Syria even less likely.

This is a point Defense Secretary Jim Mattis and others in the administration have stressed in recent days, according to the New York Times, noting that a complete withdrawal would allow Iran (and Russia) to run roughshod over the entire country.

Those concerns haven’t swayed Trump, though, who seems adamant that the fight against ISIS is all that mattered and that it’s over. For others in Syria, the fight goes on.