The problem of picking sides, then supporting them with military hardware, is that you may have picked the wrong side. What looks right now may be a terrible mistake. America has made some terrible choices in the past, and much of their choices were made because they never really understood the political and social issues that were underlying to each side.
Saudis warns U.S. that 9/11 responsibility law would erode investor confidence in America (Reuters)
from the article: Friends of Syria group agrees to give urgent military aid to rebels