Many of the politicians that oppose President Bush are giving aid and comfort to the enemy. By their speech (and in some cases their actions) they are directly encouraging the enemy to kill American service personnel.
They are also encouraging the enemy to hang on at any cost - at least until the election.
They also encourage the enemy with the idea that they may be able to commit some horrible terrorist act which will sway the US election (think Spain here).
I think that the Department of Justice should prosecute when appropriate.