Do not "fix" what isn't broken, especially if your idea of fixing something unbroken is to break it.
If you make it harder for good people to get weapons, only bad people will get them because they'll ignore the rules.
Maybe, just maybe, if nightclubs had to let people bring guns in while they drank, we'd have brought something like what happened here or at the Pulse to a quicker end. I doubt it, but for the benefit of argument, I'll entertain the possibility. What is not in doubt that we would easily have vastly more shootings happening at nightclubs than we already do, more than enuf to more than offset any possible savings in human lives from such a policy, but because at most such shootings would only make the local news, it wouldn't create the uproar which I guess is what you're wanting to do. As tragic as what happened here and at the Pulse is, more tragic to me are the thousands that die each year in ones or twos all over America. That and not spectacles such as these is what any change in gun policy in this country needs to address.