Well, here's how politics works in an adversarial (partisan) system:

The incumbent defends everything he ever did...positive statements...and attacks his opponent over various supposed weaknesses and fallacies...negative statements.

The challenger attacks everything the incumbent ever did...negative statements...and proposes things he would do instead if elected...positive statements.

The only reason that everything Kerry says sounds negative to you, Old Guy, is that you don't like Kerry in the first place. If your primary dislike was for Bush, then you would see it the other way around, and everthing Bush said would sound negative (or stupid) to you.

It's subjective, according to one's initial partisan prejudices. And that is the disease of party-driven politics.