The shooting at the Holocaust Memorial Museum in Washington, D.C. was a very short event. It was stopped by a man with a gun protecting the rest of the people in the building. In Washington, they have lots of armed guards. In the rest of the country, and especially in schools, there are no armed guards. A crazy can walk into a restaurant or museum anywhere and there are no protectors to stop their mayhem.
I am so very sorry that yet again, we read about someone moving from hateful words to murderous actions. I want us all to be mindful though, that an armed person protected many many more than were shot. The spread of armed citizens with concealed weapons can make us all safer as we come and go in public. History for the last 10 years shows us that armed, law abiding citizens don't add to the chaos or crime. How many citizens with a concealed carry permit have gone around the bend and done a murder spree? I have found none.
Even those who don't want to get involved in guns should promote the rights of those who do, as they benefit from the drop in violent crime in those areas where gun ownership increases. Sheepdogs protect themselves and the sheep.