The base is that free is not, never has been, and never will be safe. There is inherent dangers associated with freedom. You use government on some level reactively in order to for the most part keep it cleaned up. But we'll never make it zero, particularly in a free state. So instead of saying something of the sort of "restricting guns makes us safer", we have to consider the erosion of our rights. Perhaps making guns illegal could make us "safer" by some metric, but is it worth giving up our freedom over? Once you set a precedent for government action, it's going to run with it for as long as it can possibly get away with. Once you say 1 right for safety, government is going to be looking at all rights. Cost analysis is fine on the local scale, but everything must be related back to the global scale as well. We have to understand the nature of government and the road it will take when we consider expanding its power. If we do so haphazardly, the consequences are going to be extreme and beyond that which was intended. Getting it back ain't gonna be so easy either.