Judging from the past examples, they'd be corrupted at lightning speed - who wants to risk their life in some foreign country by playing a saint when all local "government" officials around you are on the take? What would motivate one to resist? The locals have patriotism, caring for their community and making better country, but foreign forces are just paid to do a job - so somebody could pay them 10x to do a different job or just to look the other way. It happened to UN forces many times.