Why the United States is not able to return to Syria?

US President Donald Trump said that the US troops are being withdrawn from Syria soon, but it is not possible to implement it right now. Because there is the risk of militant organization IS.
On the other hand, the new polarization in Syria is due to Russia, Iran and Turkey's position. In all, the complexity of Syria is increasing. The question is now whether the US troops will be able to return to Syria immediately, if they want trump in this context.
It has been found that Donald Trump said last week that the US troops would be quickly evacuated from Syria. He changed his position in a short time.
US officials say the talks with the Trump Security Council and advisers have come under discussion about the risks of militant IS IS. And in this discussion advisers have been able to convince the trump about the risk of IS. That's why he has stepped down from the position and has agreed to keep the US troops indefinitely in Syria.
There are about two thousand US troops in Syria. In Eastern Syria, the combined forces of Kurds and Arab militias are fighting against IS in the name of the Syrian Democratic Force. US soldiers working in their support
The US troops occupy East Syria with their local allies. But no one can say that the IS has been abolished. IS is at risk of IS. They moved to another area of ​​Syria. As the war ended, Trump said that the situation is not yet in the field.
USA is a vital force in Syria war. But the United States does not have the main role here. Although Turkey and Russia and Iran are supporting each other in the battlefield of Syria. But these three countries pledged to hasten the initiative to bring stability to Syria by holding a high-level meeting.
Their position is said to be new polarization. They gave the indication that the country's three soldiers will have a long time in Syria. In such circumstances, the US soldiers may have to remain in Syria indefinitely.