When these things happen there is seldom a lack of ideas and suggestions about how to correct thing or make things safer, which is a good thing, but in this case, EVERYTHING was there for this to have been prevented from happening. One man did what he was supposed to do by notifying authorities when he saw things that sent up the red flags and he did so just about a month ago, and somehow all things that should have worked failed. Sometimes you have a case that slips through the cracks and this one horrendously did. This could have been prevented and some people are having to live with the fact that they didn't do their job or fell down on their job and as a result, 17 innocent people died.
If people want to do away with or modify the 2nd Amendment then there is a Constitutionally prescribed way to do that. If the American people decided to do that then it should be by that very procedure and if it doesn't pass then that decision should also be accepted. In my opinion, though, even doing it by the Constitutionally prescribed way, if it passed and surely if it was attempted by any other way would it potentially put our nation in another (un)Civil War for there are many freedom loving people that will not relinquish their weapons to the Government regardless of how it comes about. This still will not stop mentally deficient people from doing horrendous things for this boy had been studying how to make bombs and given enough time could have perfected doing that and could have potentially killed or injured more.
If eliminating the instrument stops the violent act from happening then why don't we eliminate alcohol again as many more innocent people die annually from drunk drivers than from legally obtained guns?
From David's Soapbox .. dated article though
This one says Alcohol 3 times more deaths
There are things that can be done to help reduce gun violence and those stem around following up on tips and warnings like was given. Paying attention to all the checkboxes that are so common with people like this boy who did this. Beefing up and strengthening background checks and doing more to prevent mentally ill people from ever obtaining firearms.