The rub is that we no longer have the facilities we once had. In the 1980’s Reagan shut down the last of the federal mental institutions. The states who were supposed to build and staff facilities to take up the slack, didn’t. So there is a shortage of facilities, and people to treat them.
We don't have the beds, and we can’t just lock them up in prison and hope for the best. Prisons are overcrowded too, and the medical care in prisons is worse than the most awful example of mental hospitals.
That’s the problem. Even if we started to focus on mental health, we couldn’t hope to do anything for at least a decade. It would take time to build the facilities, and moreover, training enough Doctors would take years.
So to get started now, would cost billions, and not show any results for a decade, or two?