“Over the past decade the business of renting out private soldiers has grown from a specialised niche into a global trade, worth as much as $100 billion, according to the United Nations. When the American consulate in Benghazi, Libya, was torched in September, locals hired by Blue Mountain, a British firm, were on guard. When a few weeks later African Union forces kicked the Shabab, a terrorist group, out of Kismayo, Somalia, South African private soldiers gave them training and support. In Iraq and Afghanistan more than 20,000 private guards are employed by the American government.”

Source: Private soldiers: Bullets for hire | The Economist