A1Kaid:
It's true that most of the "Private Contractors" have earned a reputation of being "Cold hearted mercenaries" but that doesn't change the fact that there are still a lot of decent, honest and hard working men involved with those contracting companies. Most of them are usually ex-military personnel, family men who're there simply for the high pays. These men also have families to feed, kids to raise and it's not exactly right to label all these men as "Mercenaries".
One more thing that you should know is that these 'Security Companies' also hire a LOT of local Iraqi's who're also committed to the same 'Objectives' these contractor personnel are following. Which basically is to provide security for convoys, high value targets, and VIP personalities. And MOST of the time, they do a fine job and that's exactly why they can earn around 160,000$ in a year.