I'm a generally hopeful kind of person and tend to believe that good-will prevails and truth and beauty win out. But I feel quite sure that if the Sandy Hook killings did nothing to change the way Americans can get guns, the Orlando nightclub slaughter won't either. Sorry.
If you have some time, have a look at what happened in Australia in the wake of a very nasty event in 1996.
It may not be the perfect solution, but it shows that gun-control legislation can change things.
In a country that is not America, I guess...