how do we solve the issue of psychotics out there? Is there an answer?

I mean after today's events I wonder what the answers could be!
Psychiatric institutions are throughout Europe but in the US they have been closed down and deemed unecessary! Really!? Well I beg to differ here, some people need watching?
Serious watching, not just for themselves and what harm they could create for themselves but for others...
Drugs harm the mind, they derange facts and cloud judgements, alcohol taken in vast quantities over a long period of time also renders the user borderline.

Something needs to change, governments have to step up to the mark and protect everyone's rights once and for all.