Remember, the local government often means the thugs that most effectively repressed everyone else. Funnel foreign aid in and they'll cheerfully redirect large fractions to private Swiss bank accounts. In fact they will get quite offended if you try to object to them doing it. (They will also claim not to be while proceeding to do it anyways.)
Furthermore many of these governments don't much like us, or if they do like us, don't see their goals as being aligned with ours.
Cheers,
Ben