Zero tolerance policies, opinions?

If your goal is to har and ruin students who have done nothing wrong, then yes, they are exceedingly effective. However, if your goal is to halt school violence, and school shootings in particular, they are hilariously ineffective. As usual, the powers that be grossly overreacted to a minor threat. While we've probably done well to stop ignoring the presence of guns in schools almost entirely (watch the movie Heathers, then ponder what would happen to a student who pulled out a gun and fired blanks at two bullies in a school cafeteria in this day and age), we swung to the opposite extreme and started expelling students for steak knives or pointing fingers at clmates and going "pow pow".