"Sez you, toots!"
You're right. Blonde 4 year-olds and grannies in wheelchairs seem to invite the closest scrutiny from the TSA. God forbid that we focus on the people trying to kill us.
The fact of the matter is that a terrorist dressed in traditional arab clothing carrying a large satchel with the word "BOMB" in large white letters on the outside wouldn't be noticed by the TSA. But, try to sneak a half-used tube of toothpaste aboard an aircraft . . . . . .