Bob McManus, in an excellent column for the New York Post, considers the gangbanger-as-gunslinger issue and the crazy loner shooter issue as two sides of the same bent coin. That "coin" being the reluctance to incarcerate criminals and coercively treat demonstrated madness and addiction.
Our society currently manifests both of these related failures-of-judgment. His relatively brief column is worth reading.
My only concern about "coercively treated madness" is that, in a society as ideologically split as ours, one side might decide to treat all on the other side as deranged and lock up half the country.