Obviously, these two groups are supposed to be on the same side, but communication and coordination are poor between the uniformed military and private forces. And it's not hard to see why a Marine would be resentful of the situation where private security guards receive 5 times the pay for work similar to what he (the Marine) is doing: roughly equal in status (these contractors aren't just doing laundry and serving meals, they are doing "mission-critical" work in many cases), and if anything probably lower in personal risk (which is a relative statement--no American in Iraq is safe).
The main source for the NPR story is an ex-Marine who left his job as a firefighter to go to Iraq in the employ of Zapata Engineering. He's completely upfront about his reasons for taking the job--$$$$--and he's retained a lawyer in the wake of his run-in with the Marines. The US government has banned him from further employment in Iraq. The Marines are flatly denying the charges these detainees are making, and Zapata flatly denies the military's claim that the Zapata guys fired on a military position first. This really doesn't sound, all in all, like a simple misunderstanding by like-minded people in fundamentally friendly organizations.
Chris Hedges, writing about our troops in Iraq:
The young soldiers, trained well enough to be disciplined but encouraged to maintain their naive adolescent belief in invulnerability, have in wartime more power at their fingertips than they will ever have again. They catapult from being minimum wage employees at places like Burger King, facing a life of dead-end jobs with little hope of health insurance and adequate benefits, to being part of, in the words of the Marines, "the greatest fighting force on the face of the earth." The disparity between what they were and what they have become is breathtaking and intoxicating.
The disparity recurs on the other end, when the soldiers muster out and return home to a mundane job with low pay and dim prospects. This Zapata employee was a firefighter, but it must not have paid a middle-class income, because he jumped at the chance to go to Iraq as a mercenary. I know the Army and Marines and National Guard are having terrible trouble meeting their recruitment quotas of 18-year-olds, but I bet that the private security firms have a lot less trouble hiring. There's the money, obviously, plus I believe there are plenty of 35-year-old former soldiers who are itching to get back in the action. Making an unscientific judgment from the military vets I've known, it seems that military service in the all-volunteer era creates a class of folks whose only skills are tough-guy skills. The only jobs they're qualified for, and the only jobs that stimulate them the way active military duty did, are jobs as police officers or firefighters.
And this has repercussions, incidentally, for the profession of law enforcement. Some young men today are advised that military service is the ONLY appropriate preparation for a job as a police officer. Again, I'm going on media images and my limited experience, but it seems domestic US law enforcement is much more military-like than it used to be. Cops don't wear neckties and brogans or carry nightsticks. They wear Kevlar and combat boots and carry M-16s.
As Matthew Yglesias observed recently in a completely different context, the wholesale replacement of government employees with contractors, ostensibly to reduce government and control expenses, is a ruse pioneered by Republican administrations and validated, unfortunately, by the Democrats under Clinton. Not only is the government not saving money this way, but they (the Republican-controlled Executive Branch) are rewarding a GOP-friendly company, and ensuring that some of the tax dollars going to fight the war, will ultimately flow into GOP campaign coffers.
I'm talking myself into being an advocate for a national-service draft. Be all you can be? Learn computers? My ass. When I think about it, the notion of the military as an avenue of upward mobility, or a place for young people to obtain marketable skills, is a bit troubling. De-professionalize and, by all means, de-privatize the military. (Reason # 103194 why I will never hear the words "Senator Dix.")