I found it interesting to read the comments on the blog post where the TSA announced they would stop confiscating pocketknives (effective April 25): http://blog.tsa.gov/2013/03/small-pocket-knives-more-support...

Instead of celebrating this as a victory for common sense, many commenters argued against the change, claiming it would make flights less safe (or at least feel less safe). I think these people are representative of a significant fraction of the population who think the TSA's work is both necessary and effective, and would oppose limiting it any further.