Conversation so far:
How many school shootings have there been in the US since 2009
CNN shared data which showed that over the previous nine years, the U.S. had experienced 288 school shootings.
why are there so many school shootings in the us compared to other developed countries
Studies have linked stricter gun laws to fewer gun deaths. But the US has the weakest gun laws in the developed world.

Question: what promted the law to change in the 60s
Self-contained rewrite: what prompted the gun law to change in the 60s