Answer:
There has not been any effective changes to the middle east region with the presence of US troops. A lot of forces of the US have been posted to Syria for the fight against the Islamic state where the rationale has gone beyond deployment. Iran threats have bought minor changes to the military presence, the position of US has only been hyped rather than any substantial change around. Many troops have returned to Saudi Arabia demonstrating recent changes to force posture in the region which has also been very low.