A good addendum to this post is Jason Fritz's look at the positive role of trained and competent police in places like Egypt:
[Exum] is right in the gist of his post - if we're invited to help these newly-democratizing nations, we should start with the police. I diverge from his position in that we shouldn't start a training program, we should initiate a police development program (again, if invited to do so). Funding-wise, a small team of police development experts that help the Egyptians revamp their police structure, policies, and police academy curriculum would provide dividends much greater than the investment. This should be our focus in the region, not military aid, which is expensive for the USG and provides little return in stability or U.S. national objectives.