I pointed out one big reason up thread; Uganda imports more from the US than it exports to the US and so it is in our interest to keep Uganda stable. In addition, an educated citizenry is always the best protection against oppression. Education reduces the need for emergency aid and also reduces suffering by teaching proper farming and distribution techniques, health care.
As I have said before, IMHO the biggest threat to humankind today are the US Biblical Christian Fundamentalists and this thread is just another example of how insidious and evil they really are. The proper response to their efforts to teach is not to deny them passports or restrict their efforts but rather to educate the audience so that no matter where in the world they try to peddler their Snake Oil they are greeted with laughter and derision.
Anyone so limited that they can only spell a word one way is severely handicapped!