What about America though, where most of these mass shootings aren't terrorist attacks? If both sides are stupidly wrong, then how could we proceed to something better?
They are terrorist attacks first off. (The only reason the Vegas story turned from "Terror Attack in Vegas" to "Mass Shooting in Vegas" is because they discovered the terrorist was white)
Second, I'm going to take both sides to their extremes for a moment.
Total gun ban, would require a lot of man power to accomplish. You are going to have to either have the national guard, or other military body do a sweep of every home in the country, otherwise the ban is pointless as plenty wont give up their weapons willingly. There will be a lot of shootouts between citizens and military as well, from people who'd rather fight than give in. This isn't for a bad reason either, as situations like
Waco texas are all the evidence some people need to believe that martial law is coming, and weapons confiscation would be seen as the last step before it was imposed. A disarmed country cant fight back very well after all.
After the months of chaos, criminals would still have easy enough access to weapons, brought in from mexico, or if that is cut off in the operation, other ways, not to mention the plethora of weapons that would have been hidden. Someone who is interested in causing damage to the civilian populace would have to look to a weapons smuggler, and that smuggler is going to have access to a lot more deadly toys than a semi-auto rifle with a bump-fire stock. Full auto toys, probably some explosives too.
Result: Terrorist is probably going have better equipment to kill with, but attacks will most likely be much less frequent due to easy access to civi-arms being gone. Semi-effective
ARM EVERYONE The NRA's wet dream will be much shorter a type. Lets say the NRA gets their way and everyone from school teachers to sanitation engineers are packing a .45. This leads to a situation similar to the cold war, nuclear deterrence and whatnot (Or to simplify, "I don't want to shoot you, because you can shoot me back") which would be great at first. This leads to problems though. It's much easier for people who aren't fit to steal or otherwise get a gun with so many in the open.
The main problem though is the same as with Nuclear deterrence. The country would be a ticking time bomb just waiting for the right people to end up together. All it would take is one jumpy kid, and times square could turn into a flashpoint, with everyone opening fire on perceived attackers when those attackers are actually doing the exact same thing they are. The result would be countless dead, even more injured, and a whole lot of spent brass that needs to be cleaned up.
Result:
maybe less small time violence, as criminals might think twice on drawing one someone when that person can draw right back on them. Country loses the need for a terrorist to even attack, as it becomes a tinderbox just waiting for someone to throw a match and we'll give ourselves a tragedy. A little bit effective?
So that leaves me with both sides wrong. But that still leaves the question of if both are wrong, how do we go forward. And that is by figuring out a third option, whether that be better control and checks on weapons, or something else entirely, I don't know. I do not see either as a solution to end tragedy, because there is no easy way to make all this stop.
Of course I could just be talking out of my ass, and be already indoctrinated by one side or another and be completely wrong on everything I've said. All I know is I was supposed to start a road trip 40 minutes ago.