Hyperbole does nothing to add to a commentary on any issue, nor does the straw man fallacy. We have a criminal justice system that is supposed to deal with people who violate the law. Regrettably some of the more recent people who've decided to go on killing sprees have ended it by taking their own life, thus skirting the justice system, however that justice system would have only given them death, or life behind bars.
This is punishment, however, and not prevention. Can we say it is just or moral to allow the actions of others, and a very small minority of others it is, affect the personal liberties of people who have in no way done anything wrong? Stricter laws are going to do nothing to someone who is willing not only to violate laws to get what they want, but to die in the end. Much like kamikaze planes in the pacific theater of World War 2, the only thing you can do is shoot at them, and pray for the best. Do not take this as me saying that we should all be armed and shooting people to protect ourselves, so much as me saying that our hopes in stopping someone who is willing to die to do something are slim to none. Most of the time shooting at Kamikaze pilots did nothing, and they ended up sinking whatever boat they set into their sights.
Like Kamikaze, these people are born from desperation. They are born from a society that is less and less willing to comprise, and is more and more divisive and bleak. As love vanishes, only hate can take it's place. As tolerance thins, only intolerance can step forth to fill that void. These people are lost, and they need to be found. They need to be understood, and treated with the care and compassion that this culture should be placing on all those with mental and emotional difficulties. We can not just marginalize them by pretending that they are simply born evil. They are not, they are made evil (or desperate as the case surely is) because of the lives they lived, the society they grew up in, and an over abundance of media giving forth the idea that they can become famous, or that a single dedicated soul can truly change the world.
Laws will not prevent someone who ignores laws from doing as they please, they only place harsher sanctions against people who have otherwise been perfectly law abiding citizens. This is a tricky issue, it is not black and white, it is not even shades of gray. There is no single solution to this, and certainly more laws are going to have very little effect on it. It requires a social approach to seek out the root of the issue, to find out what has pushed us so far that slaughter is the only option we have left, and then to deal with it from there.
No one wants to kill, to hurt, or to destroy, until something has pushed them there. People are not born "evil".