The Pentagon has spent roughly $36 million on its initial class of U.S.-trained rebels—or $600,000 per anti-ISIS trainee. The average fighter makes between $200-$400 a month, depending on his skillset. In all, officials have allotted $500 million for the training program. U.S. defense officials recently boasted that more Syrians signed up to receive U.S training and take on the self-proclaimed Islamic State since the inaugural class of only 60 fighters. As it turns out, the new class is short of 100 fighters, two defense officials told the Daily Beast. With that, the keystone of the U.S. approach to the war against ISIS in Syria – building up a force to counter the group continues to falter.At U.S. Central Command, which is responsible for the Middle East, defense officials said that while the current pace did not portend of reaching the goal of 15,000 recruits, at a rate of 5,000 a year, the program was on the right course. Defense officials said they are having a hard time because the vetting process is nearly impossible for most Syrians to pass through. The U.S. demands potential trainees vow to not attack Syrian President Bashir al Assad forces, even as many of those trainees hold Assad responsible for the destruction of their communities and unending death tolls. And U.S. trainers are reticent to accept fighters who have fought alongside many Syrian groups as they consider them too extreme, a difficult proposition in a nearly five-year civil war.

The result: 7,000 applied, 1,700 passed the initial vetting and only 60 completed the inaugural course.

“The process is not fast, but it is thorough - and we will not cut corners just to increase numbers,” Air Force Col. Patrick Ryder, a CENTCOM spokesman explained in an email to the Daily Beast. “This is critical to the credibility of the program, and as opposition forces begin to see the quality of our students, the quality of our course of instruction, and the quality of the equipment we are providing, we will begin to see even larger numbers of high-quality volunteers for the program.”

The ongoing low enrollment levels has left many in the Pentagon frustrated, dashing already fleeting hopes for a moderate U.S.-trained Syrian army. “Our laws are standing in the way. This isn’t the good guys against the bad guys. No one is clean. How can you apply standard for training foreign militaries,” one defense official pondered.Secretary of Defense Ash Carter is scheduled to appear before the Senate Armed Service Committee Wednesday, where he is likely to be asked about the U.S. effort to train Syrian fighters. Earlier this month, he revealed the size of the initial class. "I said the number 60, and I can look out at your faces and you have the same reaction I do, which is that that's an awfully small number,” Carter told the committee earlier this month.

—Nancy Youssef