I am adding my voice to the chorus of people calling for significant gun reform in the US, a country that seems to be in greater denial than the river in Egypt. My personal beliefs aside, this is an emergency management issue, and one that will continue to be a problem until the citizens of the US decide to make a change.
Before I get too deep into it, you're likely wondering what makes this an emergency management/emergency preparedness issue. One of the treatments for an identified risk is prevention, stopping something before it starts. No matter how angry someone gets, it is incredibly hard to kill 17 people at once if you don't have a gun. Good social policies, ones that enable people and help people to move forward in the world, are also good emergency management policies. If you look after people, provide the necessities, and make them safe then you've already made them more resilient and better able to deal with an emergency.
There is no good reason for a private citizen to own a handgun or semi-automatic weapon of any type. NONE. Hunting rifles are a different story, and I have many friends who are hunters. I have no desire to stop anyone from pursuing a hobby (or in some cases, lifestyle) like hunting. In fact, many of them rely on the meat from hunting to feed their families and communities. It is time for America to admit that they have an addiction to guns, and to seek serious help for that addiction.
There are all sorts of arguments out there about 2nd amendment rights, to which I say that it isn't reasonable to expect the founding fathers to mean the right to a weapon that fires 45 rounds/minute. When your guns take 20-30 seconds to reload, then that is your frame of reference. I suspect that the founding fathers would write the 2nd amendment very differently today.
The other argument that is out there is the "good guy with a gun" argument that says only a good guy with a gun can stop a bad guy with a gun. This is a logical fallacy, because if the bad guy doesn't have a gun to begin with, then you don't need the good guy with a gun. The truth here is that the "good guy with a gun" is actually a second active shooter, one with unknown training, equipment, and who is likely not nearly as capable of keeping perspective on the situation as a well-trained police officer.
I'm aware that there are many Americans who don't subscribe to gun culture, and who are desperately calling for gun reform. I, and many people from around the world, stand with you and support your efforts to weed out this rotten part of American culture. Until the image of the gunslinger is purged from American culture, there will be no change. The rest of the world has figured it out...right now the US hasn't, and they look bad because of it.