"This army would have to have modern weapons and Special Force equipment. It could only get these from the Major Western Countries. To be effective it would have to have billions in financial add, which it could only get through the clandestine operation money of the major governments, very secretly financed.
This army could not have open affiliation with governments because of the threat of retaliation and/or treaties. Just as it is done now with private armies in Iraqi and other places, the Western Countries could support it with technology, weapons, information and logistics, and then even help finance it though secret treaties.
It could be made up of retired or trained Special Forces from