An entire generation of bitter dead enders have spent the last thirty years stewing over why we lost the war in Vietnam. Nixon's political disgrace prevented us from having the sort of rational post-mortem on the experience that may have prevented repetition of the same mistakes.
Immediately after the war it seemed like there was a broad consensus view that the real reason for defeat was getting into the war in the first place. That it was built on an unwise premise. That we interjected ourselves into what was essentially the French colonial struggle in Southeast Asia under the rubric of the Cold War. That however good our intentions may have been, we were doomed for failure from the start because we were battling a home grown insurgency (Ignoring the artificial partitioning of the country) that was always going to be able to outlast us. That we had put our military into an impossible situation. Unable to differentiate friend from foe, the only way to completely stamp out such an insurgency is genocide.
The minority view, held to passionately by the dead-enders and wingers of all stripes was that the cause was righteous. We "won every battle". We were only defeated when the country lost its will to persevere. The patron saint of this point of view is Vietnamese general Vo Nguyen Giap who's explanation of their strategy has been seized upon by the right as evidence that the anti-war movement in the US was instrumental in the military defeat in country. General Giap makes clear that they considered faltering domestic support for the war one of their prime objectives. The resultant loony paranoid delusion on the part of the right, that General Giap was controlling the anti-war movement gave us the abuses of the Nixon administration and the need to treat dissent as treason.
When the Bush administration conflates the war in Iraq, a classic war of occupation and insurgency, with the threat of domestic terrorism they open the door to a vortex of abuses that will be perpetrated in the name of defending the mission in Iraq. An entire generation of military strategists have been told that one of the primary goals of an insurgency is to cultivate ties with organized domestic dissent. Therefore dissent is the enemy. If you hand the keys of the most sophisticated evesdropping technologies available to people who believe that dissent is a mortal enemy of their war effort, bad things are guarrenteed to ensue.
So, the military has an institutional interest in neutralizing any effective anti-war movement in this country. Their doctrine has enshrined a version of history that credits such a movement with the loss of the last insurgent war in which they were involved.
The Republican political machine has shown no compunction against using the national security state to pursue wholly political goals. Consider Tom Delay's use of the Department of Homeland security to track down Democrats during the redistricting farce. Consider Plamegate.
We are through the looking glass here folks. This is as bad as it gets.