For a well-documented summary of the Vietnam War, I recommend Ken Burns's PBS documentary which came out a few weeks ago [1] It is a total of 18 hours of video but very well worth it.
To me, it is striking how history has repeated itself with the Iraq and Afghanistan wars. A war with: (1) no clear goal or victory criteria, (2) endless spending and major profiteering by the war industrial-complex and (3) low levels of support from the American people. It was very sad to, very clearly, draw the parallels between the two wars as the documentary progressed.