Hate to admit it, but you are right.
That and our constitution prevent our society doing anything BEFORE the tragedy. Crazy people and sexual child molesters have constitutional rights.
Mental illness is such a tough issue, and the more I've learned the more I recognize that often there just isn't a single correct choice or solution. So very sad.
The one change I do advocate is changing the law to get back to a better balance when it comes to deciding whether to institutionalize a person. As I understand it, unless they verbalize or write a specific threat against a person, it is nearly impossible to institutionalize them against their will before they actually act on it.