An assessment of the employment of mercenaries in Afghanistan gives mixed results. U.S. armed forces appear to have been happy with the Afghan Security Forces and ad hoc militias and only replaced them because of political reasons or because they felt that they were no longer needed. By contrast, the work of private security companies seems to have satisfied few. While in the short term no practical alternative to their use existed, it is not obvious that this option saves any money to the governments involved in the medium and long-term. Moreover, private security contractors are not subject to the control of military authorities, nor to military discipline. Their record of abusive behavior is indisputable and probably played a significant role in alienating the Afghan public. Unless much changes, the potential of private security companies in peacekeeping does not appear to be a bright one.
Giustozzi, A. Privatizing war and security in Afghanistan: Future or dead end? Economics of Peace and Security Journal (2007) 2 (1) 30-34.