Y'all have already demonstrated that you're not willing to make the changes necessary to really fix mental healthcare. How many of you would support comprehensive psychological and background checks for every gun owner? I reckon you'd just start screaming "2A!"
Here you show your colors. You are an authoritarian that seeks safety by denying others rights. You can only conceive that EVERY gun owner needs to have a background check and the EVERY gun owner needs to go through a battery of psychological tests etc.
The great myth propagated to ill informed individuals is that "no one could have seen this coming", and the person "just snapped"," [The shooter] was friendly etc. and I can't believe he did that."
When the rest of the story dribbles out, it almost always indicates a couple of things, cruelty to others (those who are cruel to animals also), a pattern of aggressive and threatening behavior, escalating tensions and hostilities, they tend to blame shift, signs of mental illness do not simply just rise up as signs of serious mental illness don't just suddenly arise (apart from drug or alcohol abuse) etc. The truth is that most people are simply not built that way naturally. At trials, you see a long train of circumstances that a reasonable person could conclude that the accused almost seemed destined to do something awful as the milemarkers of their life show.
When you crack the skull of an infant such as the current shooter and try to collect weapons to shoot up your AF base as this guy apparently did, the failure of the AF courtmartial was leniency when it was not deserved--he should have still been in Leavenworth.
The other LV shooter is an odder case where there is a lot of smoke--one is that the guy acted out a revenge fantasy or some deranged political statement for some reason, the other more unsettling possibility is that he did so in concert with others. Nevertheless, like the Unabomber, vague tales of threatening behavior, bragging about his criminal father, family dispute issues, the possibility that others in the family were involved in illegal activities, and the possibility that his money was illegally accrued, raise red flags. Even the Uzbek driver in NYC indicated over a period of months that he was building up to something--conflictual relationships, failures, seeking out a radical mosque in NJ etc.
If you are a criminal with convictions or arrests for violent behavior, you are a lot more likely than the general public to do violent crimes. If you have been committed to a mental health facility for having violent thoughts and actions, then you are much more likely to do violence to others, and so on.
Now, as others have suggested satirically above, a different person could conclude the whole problem is the 4th, 5th, 6th, and 8th Amendments to the U.S. Constitution. WARNING FOR SLOPPY READERS__THIS IS JUST EXAGGERATED HYPERBOLE TO ILLUSTRATE A POINT__NOT A SERIOUS PROPOSAL Now, like Jonathan Swift at his most satiric in A Modest Proposal , using your rationale for the 2nd, let us rewrite the Constitution: 4th, you have no right of privacy and can be searched or arrested at any time based on whims of the police, 5th You can be compelled to testify as any innocent person would do so and only the guilty would not want a chance to clear their name, a simple order from a judge should suffice to arrest you. 6th, you shall have a trial with the jury only composed of professional law enforcement, hearsay shall be allowed if in the favor of the state, no right to counsel as lawyers muck up everything, trial shall be by a panel of judges, no witnesses shall be sworn and no cross examination because all witnesses lie. 8th, Detention for as long as judges feel reasonable and no prisoner shall be released before trial, the punishment should fit the crime--cruel and depraved acts get cruel and depraved punishment.
Now, I suspect that the crime rate would drop if that was the case--even if just the 4th was more or less abolished. However, a lot of innocent people will lose most of their civil liberties simply to get to those criminals. In so doing, it is probable that we would find that like Lavrentia Beria (head of the secret police during the Stalin era) "Show me the man, and I’ll show you their crime.” Eventually, uprisings because of the inevitable injustices of the process will occur and the ensuing civil war will create crimes on a massive scale as if to balance the books.
Like Hobbes, you appear to be a person willing to surrender their rights and the rights of others to an all powerful government so that you can be "safe". Unfortunately for you, the United States and its Bill of Rights was based on protecting natural rights as the social contract for this society per Locke. These include the right to self defense and access to the tools to do so. If you reject the social contract, then I would suggest that there are plenty of other nations where you could be much happier that follow your wishes for society--Mexico for example has quite strict gun control laws or Canada which also does so.
I leave with the words of Ben Franklin, "Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety."