You actually believe that either Nader or Kucinich would   implement an "immediate withdrawal" of troops? If you do, I've got a nice bridge that you might be interested in, cheap, and in New York City--Some of us remember that Nixon was elected because he had a plan for "peace with honor", and he promised to withdraw troops from Vietnam, except for the honor part, he did it, but it took a very long time.   

Once the bullets start to fly, there is no easy way out for anybody--even if you achieve a total victory, with unconditional surrender of the enemy, as we did in WWII, the military occupation and the diplomatic negotiations go on for years--Kerry was just being honest about what would happen.