I wouldn't count all of it. If the Koch bros spend money trying to stop something from happening, that shouldn't count as a cost. But I think it's clear that most stuff proposed would probably be worth it. If you use the government human life value, the cost of 1% of the gun death in the US is equivalent to 2.4 times the entire ATF budget. Based on that, I think it's safe to say we should stick to ideological arguments because the fiscal ones just aren't there. You could double the ATF budget, pay $1.6 billion to cover pork and such, and if the number of gun deaths dropped just 1% it would be worth it...even in cold-hearted, unfeeling, numbers driven terms.