Not sure about that. People with mental issues are pretty aware they are "different" and not well, but those who are let's say Narc's or Sociopaths will never seek help for it.
It's tough to combat mental illness because of the stigma attached, but I believe if more doors were open for those with mental illness wanting help, there would be less violence.
Not sure if the government would force meds, but I guess it happens. There are so many other amazing ways to deal with mental health, but it's not an area the medical community puts the focus on.
They are too busy trying to "cure" cancer and aids and such.
More guns will not solve this problem I believe