What if it doesn't do much?
What if, over the next 10 years, it prevents, however it does it; by making it undoable for a potential assailant to obtain a gun in time before he's commited for mental illness, or gets a nanochip or a microchip implanted into his brain, or however it prevents it - what if it prevents only one tragedy?
Wouldn't it be worth it?
Well "worth it" is a nebulous term. In terms of human life, in my opinion, of course, it is worth it. How much is a life worth? Ask an abortionist, a priest, Dr Kervorkian, or Champ and you will get a different answer from each.
My opinion is that it is worth whatever its success rate is in saving lives. Could and should be priceless, right?
. . . but here is where we could differ. We don't have infinite resources to put towards solving this problem. Would you agree on that? If we are talking about some idyllic world, where we do have infinite resources, then I say do it all.
If you have limited resources to put toward helping to curb violence, and implementing some relatively easy things will provide a much greater success rate than the X billions of dollars it will take draft, lobby for, pass, and enforce a ban, you tell me - is it worth it? . . . or would it be better to get the most "bang for your buck"? This is a decision that is made all the time in Congress, and unfortunately one that can not be avoided if we are talking reality here.
From what you have said, though, your expectation for the number of saved lives for your X billion dollars that you spent may be very different than mine, and if that is the source of our disagreement, then I guess the argument will continue.
. . . but if human considerations are all you have to go on - you are damn straight it is worth every penny and more.
In reality, that isn't the case we have here is it?