According to a news report I read, several of the teachers had state carry-concealed permits, but were required by Ct state law [Gun-Free School Zone] to leave them at home...
IMHO, a program for teachers, and other institutions (Post Office, etc), similar to the airline pilots program would be a much more effective way to deal with situations like this...
In a related vein, the Japanese loonies released Ricin gas in a subway, but no one has recommended the ban of chemicals; in Guatamala some years ago, a cane farmer went on a rampage with his machete, but there were no cries for banning machetes; and more examples abound throughout the world & through the years...
One newsman on TV advocated screening individuals for anti-social tendencies...Yeah! Let's do that! Let's set up camps to send them to!