This question is really too broad for a good answer in the kind of space we have here.
I would suggest that you are going to need to break this up, at the very least, into looking at the Cold War era and then at the era after the Cold War. You can argue that the post-2001 era is actually separate from the time between 1990 and 2000 as well.
During the Cold War, US foreign policy of course revolved around the containment of communism. As far as analysis, you could say that the policy was effective in that communism more or less died out. At the same time, you can criticize US foreign policy for its lack of attention to human rights -- it was willing to support pretty much anyone as long as they weren't communist.
After 2001, US foreign policy has been mostly concerned with fighting terrorism. To this point, foreign policy has been caught up in the wars in Iraq and Afghanistan. These wars seem not to be working, but I think that it is too early to definitively analyze whether current foreign policy is working.