You can flag, but a lone flag is worthless. Not sure how many it takes to nuke a story or comment.

For myself, I only downvote/flag stuff that I consider harmful to the community.

That does not include stories or comments with which I disagree. In fact, I frequently upvote comments posted, that attack my own positions, if they do so in a reasonable manner. Groupthink sucks, and I frequently change my mind, based on orthogonal feedback.