A couple months ago the Trump Administration revealed that they planned massive mission creep in Syria, with the objective of getting Iranian forces out of Syria.
The fly in the ointment has been Turkey's hostility to the Syrian Kurds, our primary allies in Syria.
So the other day we took a step to address that.

The U.S. military will begin putting observation posts in northern Syria to help Turkey secure its border from the threats wandering through the war-torn country.

The move could prevent skirmishes in areas near Turkey’s border from distracting U.S.-backed fighters from their mission to defeat the Islamic State. The buildup, though, could draw the ire of U.S. lawmakers, some of whom view the mission in Syria as drifting away from the original goal of defeating ISIS.

While this is being done to protect Turkey, it leaves our mission in Syria open-ended.
There is also the problem of Turkey opposing it.
If that wasn't complicated enough, the Saudi/Gulf coalition has decided to send their own troops to U.S./Kurd-controlled Syria.

Saudi Arabia and the UAE have sent military forces to areas controlled by the Kurdish YPG group in north-east Syria, Turkey’s Yenisafak newspaper reported.

The paper said the forces will be stationed with US-led coalition troops and will support its tasks with huge military enforcements as well as heavy and light weapons.

Quoting the Syrian Observatory for Human Rights, the newspaper reported that a convoy of troops belonging to an Arab Gulf state recently arrived in the contact area between the Kurdish PKK/YPG and Daesh in the Deir Ez-Zor countryside.

This comes at a time when Ankara is preparing to launch an expanded military operation with the Free Syrian Army against the Kurdish PKK group in the northeast of Syria.

Recall that Turkey sided with Qatar against the Saudi embargo. Now the Saudis are siding with the Syrian Kurds against Turkey, and our troops are in the middle.

Meanwhile, rebel forces in Idlib province have united under al-Qaeda.

While the conflict in Syria has largely faded from the news following the Idlib demilitarization agreement primarily brokered by Russia and Turkey in mid-September, a new Syrian military report cited by Al Masdar News claims that the Syrian military is set to begin a long-anticipated, major military offensive to retake the Idlib province from rebel groups.
...Last Wednesday, American-born ‘journalist’ and al-Nusra Front “media man” Bilal Abdul Kareem published a video on YouTube in which he interviewed al-Nusra Front/HTS spokesman Abu Khaled. In the video, Khaled states that “all factions” within the Idlib province have now formed a “joint operations room” to plan military operations, increase military readiness, and strike any person who seeks to contact “the [Syrian] regime or its Russian cronies” with an “iron fist.” Khaled added that this cooperation includes “all factions [in Idlib] without exemption” and that this was the “first time” that all Idlib rebels had united under one banner.
Yet, even though HTS itself has admitted that all rebels in Idlib are now under its command, it remains to be seen how the U.S. will react to an upcoming Syrian military offensive targeting the province. Indeed, prior to the demilitarization agreement reached on September 17, the Trump administration threatened to attack Syria for “any attack” it launched against Idlib, whether or not there were allegations of chemical weapon use.

So besides working alongside Saudi Arabia in Syria to protect the Kurds against our NATO ally, Turkey, we are also prepared to bomb the Damascus government if they attack al-Qaeda.
If that wasn't complicated enough, Turkey established 12 military observation posts in al-Qaeda-controlled Idlib province to protect the region from Damascus.
So we are both on Turkey's side and against Turkey's side.