The United States went to an "all-volunteer" military in 1973, and despite the fact that since that time, the United States has been involved in a multitude of adventures and misadventures, abroad; the conscription that once existed, for previous wars, does not currently exist, and seems to be something that does not appear to be returning anytime soon, which actually is pretty amazing. Whether this is good or bad, is up to a given individual's viewpoint, but to a large extent it is a heck of a lot easier to have an all-voluntary military, when that military subcontracts out to non-United States citizens, all sorts of activities that traditionally would be performed by United States soldiers. In fact, those that perform those duties for the United States military, aren't just those that are performing kitchen duty, military support, janitorial work, and the like, but are actually also directly or indirectly involved in the killing so done in wars.
So then, those that are part of our military but are also not considered to be a direct member of that military, are those that have essentially been subcontracted to that military, and therefore are not entitled to the normal benefits that are so provided for United States soldiers, such as health care, vacations, housing allowance, and the like. So too, reported deaths of United States soldiers are only those soldiers that are classified as such by the United States; whereas those brave men and women that die in the service of the United States but are considered to be temporary labor so hired, are not accorded that same sort of respect.
Somewhat surprisingly, when it comes to the subcontracting of labor to the United States military, the biggest beneficiary of such is not actually the United States military, though they do benefit; but rather are instead the management team so profiting as the representative subcontractor, thereby signifying that the people that labor for those subcontractors and are paid directly by them, are actually the ones that benefit the least, because their labor has been marked up by the subcontractor in order for that subcontractor to make a profit, upon their toil.
There are a multitude of people, all over the world, that are in need of employment, and some of those have the skill-set so desired by subcontractors to the military, such as the need for translators, construction laborers, logistical knowhow personnel, and the like, who offer services to the military infrastructure of real worth. Further to the point, there are plenty of people that are un-favored within their own nation, because they are not the right nationality, nor the right religious sect, nor financially secure, nor this nor that, which makes them susceptible to the siren call to work for the most powerful nation that the world has ever known, though only as temporary labor.
What we so have, then, is essentially a group of unseen men and women that support our military, but are not actual United States soldiers or personnel to such; but rather are guns for hire, as well as the intricate support apparatus that is so needed for the sophisticated and the often protracted wars of today. These are the new mercenaries, some of whom are risking their lives for the United States, though they are not in the direct employment of such; but rather are subcontracted to the United States, to do what they are instructed to do, come what may.