At present, the privatization is entirely in non-combatant roles. Housing is privatized, for example. Base services are increasingly privatized. Social services, big chunk of medical/dental; even at the Battalion level, the Army has contracted civilian admin officers to replace the S-1, and Marines have contracted civilians to serve as the Family Readiness Officer. All of these jobs were previously staffed by uniformed servicemembers under oath.
You may read reports about contractors carrying weapons in combat zones. That is also true; they cannot, however, be used in offensive operations by law (and ROE). For example, civilian truck drivers may carry weapons while in convoy to resupply remote locations, but only for defensive purposes and they are attached to military escort. Under no circumstances are they to engage the enemy, and we kick people out if they do. If they come under fire, they are to defend themselves and their equipment.
So what about all those civilian looking guys way forward we read about, maybe even see pictures of? I am aware of other agency contracted individuals involved in specops in an intel or technical support role. Since the 90's fielding of new military gear has changed to where maintenance contracts are not serviced internally. So if you have an advanced video security system at a FOB, the government contract requires the vendor to service the unit in the field ... even if its Kandahar. So Chuck the Nerd straps on a sig, takes a bumpy ride from Fobbiton to Ft. Apache, hits reboot, takes a return bumpy ride back to his Can with AC, Internet & Cable, for $150K a tour. Same same for tactical site exploitation, bomb forensics, etc. The military does not have the organic expertise to do the job the "new" way of war requires (like law enforcement), nor is it able to fix its own gear.
Bottom line is we have no privatized combatants. That's not spin, that's actual truth - the law is clear, Geneva is clear and its so heavily scrutinized that violation is next to impossible. Blackwater is a perfect example of the fact that when mistakes are made, they are corrected.
But TM7 I think you're wise to be skeptical. I wouldn't look at the traditional armed forces though - policy is neutering us to a peace corps with expensive gear. If one were really paranoid they might also think that the perpetuation of Afghanistan might be eroding the combat effectiveness of patriots (physical attrition and amputation) under oath, who might present the biggest threat to a privatized force employed for homeland security enforcement. Vietnam had that effect whether it was intentional or not; lot of lives were cut short or severely hampered that had they survived may have been a voice of opposition to several agendas in our society. Or maybe not ...