You can't lose what you lost long, long ago. During the Kosovo campaign, Clark on three occasions wanted to take actions that would have provoked war with Russia. Not a trait you would want in a president.
Hillary supported Clark originally and I would suppose it was his military background since we would look at her as a ridiculous Commander in Chief. It was why she wanted to be on the Armed Services Committee and as she said "I want to know what I'm talking about". Don't think she realized that Clark was so controversial....pretty dumb for being the smartest woman in the world. (Yeh, right).