“The use of mercenaries in warfare has a very long history—much longer, in fact, than the almost-exclusive deployment of national militaries to wage wars. Before the Peace of Westphalia in 1648 ended Europe’s Thirty Years’ War and marked the rise of the modern state system, medieval powers from kings to popes routinely hired private fighters to do battle for them. As state governments sought a monopoly on the use of force within their territories in the 17th century, however, they moved to stamp out violence by non-state actors, including mercenaries, driving the industry underground.
America’s reliance on private military companies in Iraq and Afghanistan over the past decade hasn’t just expanded the industry; it’s also started to change the conduct of international relations.”
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