after viewing the clip...
he is bashing bush before the comment.
he is bashing bush after the comment.
It really appears that he was referring to Bush getting us 'stuck' in iraq. It would be odd for him to immediately move from bashing bush to insulting 140k soldiers, back to bush without missing a beat.
it wasn't the smoothest speech, and I can't stand kerry one bit, but objectively speaking, he was talking about bush, not the troops.