The statements aren't false ... they're just incomplete. I will modify for clarity as follows:
The only people who owned a handgun in the 1950's and carried them around in public were law enforcement, security guards, people who enjoyed a visit to the firing range and/or engaged in competitive shooting, and criminals.
And:
Back in the 1950's, all law abiding citizens knew how dangerous and just plain stupid it would be to carry a gun around in public, loaded or unloaded.

Best,

RTD