Now I'm sure most posters to this forum are loathe to admit this, but there were three forces for change that forced the US to withdraw from SE Asia: the street protests organized by a movement of deeply committed dissenters making the country ungovernable, the mainstream media, and the anti-conscription movement.

Yes, there I said it--the mainstream media. They beamed lots and lots of pictures home that turned the tide against the war: My Lai massacre, our children being killed and wounded, Vietnamese children being killed and wounded by our children, Buddhist monks self-immolating in the streets of Saigon.

The mainstream media isn't showing the world those pictures anymore. Which makes the 100 year war theory such an enticing possibility.

And the street protests--Kent State was the high watermark that exposed the true nature of Nixon's & Hoover's 'law and order' campaign. But there were also political assassinations galore in that era that contributed to people's sense of uneasiness about government excesses and overstepping their bounds.

Finally, guys just stopped reporting to their draft offices and showing up for induction. If you lived in a big urban area, you could easily just not show up, and it would take them a LONG time to find you. Or towards the end, you had the ability to work the system by filing for conscientious objector status, which dragged out the process too.

The government's involvement in pulling out of SE Asia was Henry Kissinger's involvement in the 'secret' peace talks to allow Nixon to claim 'peace with honor'. Which dragged the war on endlessly and needlessly.

Obama/Clinton/McCain. Pick your poison, but none of them will end the war, at least in a first term.