Not Kerry. He is making it the cornerstone of his campaign (an odd thing for him to do considering his VVAW activism).
He put the light on it, and now we find out that he got out of Nam (early and for curious reasons.) People start wondering what was up. And then you got a lot of people saying he ain't no hero. That's huge.
Kerry's people know the ad is so damaging that's why they are waging a scorched earth campaign against real heroes.
You don't know what you're talking about.
It cuts into the heart of his campaign. Then when you talk about Iraq he is done. Kerry will be denied the refuge of Vietnam. He can't say, "Yeah, my record in the Senate is lousy, but I went to Nam" "Yeah, I voted against the troops in Iraq and Afghanistan, but I went to Nam"
Nam was always a mixed bag for him given his incredibly questionable antiwar actions. Now we know he was there for a little amount of time, he cheated to get medals, used his medals to get out early, went hardcore antiwar to make a name for himself politically, threw away his medals, and now all these years later he is running on those medals and acting like Nam was WWII. It paints a really bad picture. he looks like an opportunist and a phony. It reeks.
You forgot to add - "sKerry was asked to leave VN following his 3rd Purple Heart, by his fellow Officers' concern for their own safety".