Australia says you're wrong. Many Aussies bitched a storm when the conservative Howard government said enough with the mass shootings and introduced wide ranging gun control. Now, they see the world didn't end, and you can still buy (most) firearms. Aussies attitudes aren't really that different from Americans, so I call BS on the other posts suggesting it's apple (pie) and oranges.
As for criminals and laws: 1) we have laws against murder, yet murders still occur. Thus, we shouldn't regulate murders? 2) criminal gun ownership is a dynamic process. Unlike law-abiding citizens, criminals engage in conduct which puts them in regular contact with the legal system. About 700k guns are recovered from US criminals annually. *If* the US required an adequate gun safe (like Oz), *if* current gun sales laws actually got enforced, and *if* there were adequate registration of sales, the main conduits for criminals' firearms would dry up: sales from gun shops, and thefts from homes.