Since late 2015 more and more Western special operations troops have been quietly sent to Syria to provide support for the more effective rebel forces. It had been noted that air strikes were much more effective if you had more local informants and relaxed ROE (Rules of Engagement) that now ignore the use of human shields and have caused a lot more ISIL casualties. But while the ROE for air strikes was loosened up the ROE for the use of American special operations troops in Syria were made even more restrictive. In short, American commandos are to avoid getting killed or wounded while in Syria and that is their top priority. This ROE is, like many restrictive ROEs, mainly in response to political pressures not military necessity. The U.S. special operations commanders have been told that their career prospects are ruined if any of their troops in Syria get hurt. Russia and the Syria government (which Russia and Iran support) has been trying to exploit that by deliberately bombing any rebel base they suspect American special operations forces may be operating from. This Syrian ROE is very unpopular with American special operations troops (and commandos in general). Another unpopular policy was recently leaked detailing how American military intelligence officers have been ordered to falsify their press releases on progress against ISIL in Syria and Iraq to make American operations their appear more successful than they actually are. Discussion of the ROE is, of course, off limits as a matter of course as knowledge of it can give the enemy an advantage. But the enemy can quickly figure out what the basics of the American ROE is and quickly exploit it.
In spite of ROE problems the American and allied (NATO and Arab) special operations forces in Syria have made a difference. In northeast Syria American trainers working with Syrian Kurds reported a growing number of Arabs are volunteering to join the Kurdish dominated (and U.S. supported) SDF (Syrian Democratic Forces). For over a year about 80 percent of the SDF strength (currently about 25,000) was Kurdish with the rest being Christian and Moslem Arabs. But with the weakening of ISIL because of battlefield defeats and growing desertions (and fewer new recruits) more Syrian Arabs are willing to fight and prefer to do that with the SDF, who are the most successful Syrian rebels. Many of the new volunteers have no military experience at all and the U.S. is hustling to expand its training program, which takes longer for men with no military experience. In addition to the Kurds, the other reason the SDF is so effective is its attention to training and leadership. Unlike ISIL and the many militias in Syria, who provide very little (a few weeks at most) or no training for new recruits, SDF provides two months or more and refuses to accept anyone who cannot successfully complete the training. SDF has been carefully advancing towards the ISIL capital (the eastern city of Raqqa) since late 2015 and is preparing to make a big push to actually capture Raqqa. Some 5,000- 10,000 trained fighters are needed for this, plus lots of air support. The American led air coalition will deliver the air support and teams of American air controllers will be provided to make sure the air strikes are as timely and accurate as possible. Most SDF fighters are busy defending territory they already control (nearly 10 percent of Syria) so mustering a force large enough to go after Raqqa has not been easy. Another advantage SDF has is that they will cooperate with government forces when it is mutually beneficial. That usually means dealing with Islamic terrorist groups, usually ISIL.