The word for the day is "mercenary." If you can't get past the negative connotations of that word, please substitute "soldier of fortune" (SOF) or "Private Military Contractor" (PMC).
Over on Post-Modern Pulps, Jack Badelaire has a thoughtful, intelligent post about the Expendables and another flick I haven't seen (Machete). The Expendables is a throwback action flick in which macho mercenaries happen to be the heroes of the story.
At Reflexive Fire, the other Jack reviewed Eeben Barlow's book about Executive Outcomes, the mercenary organization he founded. A good read by itself that made me want to read the book, it also has blog comments from Barlow himself, as well as Wayne Bissett, who wrote Chronicles of the Mexican Horse Thief, about his time as a merc in the early days of EO, in Angola. While I don't agree with his anti-Christian sentiments, Part 1 of Chronicles is an informative and entertaining read.
While doing the research for my novel, Hell & Gone, I studied up on 20th Century mercenaries. I unearthed paramilitary magazines from the '80s, books from the library, documentaries for the History Channel, and, of course, web pages and sites devoted to the topic. This is when I learned about Executive Outcomes--an amazingly successful paramilitary force which became a victim of politics because of their success. Their track record was even more impressive than Five Commando and the Rhodesian merc units (which themselves were far more effective than any other mercenary operations in Africa up until EO).
I explored the subject because, as I envisioned the story, the CIA's SOG teams would be busy operating in preparation for Gulf War II, and mercs would need to be used as a means of providing some "plausible deniability" of US State Department involvement in the mission. Initially I had most of Rocco's Retreads recruited through Military Personnel Resources, Incorporated, but later replaced them with a fictional PMC organization to avoid offending anyone in MPRI. Like 95% of real-life mercs, most of my characters are veterans of national armed forces who found out they are good at war, and/or like it on some disturbing primordial level.
As it turns out, I hardly used even a quarter of the research I did. Yet the topic still interests me. One day I'd like to write a novel set during the conflict in the Congo during and after the Belgian pull-out. And, of course, there's the possibility of a Hell & Gone sequel that keeps coming up, even though I never imagined one when writing the book.
Mercs have a bad name in the public perception--with good reason in some cases. With some of them it's really as simple as killing for money. But there have been some idealistic mercs, "good guy" mercs, and others who just happen to be good soldiers with no army to serve in (or allowed to serve in anymore, as happened to some SADF veterans, for instance).
During part of my training WAAAAAAAAAY back in the day, me and a whole company full of other snot-nosed kids just out of high school sat through a phony briefing by a fake Soviet officer, meant to motivate us I suppose. Anyway, this guy asked how many of us had received an enlistment bonus. To everyone who raised their hand he said, "You are nothing more than mercenaries."
The truth hurts, even when uttered by a fake Russian soldier. The majority of soldiers, sailors, airmen and marines sign on the dotted line because they want job training or college money. (As someone who joined out of patriotism primarily, I was a supreme oddball.) When it comes down to it, most of them will do whatever they're told to keep out of trouble and get that money and job training, even when it violates the Constitution they swear to defend or when they just know, deep down, that it's wrong. How is that any better than what a soldier of fortune does?