As I've said before, I don't get this idea that we should strive to act like that darkly funny scene in Terry Gilliam's
Brazil, wherein the patrons and staff at a bombed restaurant attempt to continue dining as if nothing has happened.
Let's suppose that some terrorist group became skilled enough to bomb a major sporting event or other large concentration of people every six months or so. Not big bombs, mind you, just enough to kill a few dozen or a hundred people each.
By the strategy seemingly being argued for here, a "resilient" or "rational" America would just let the existing police do their work as best they can, maybe with some not-too-expensive Federal assistance, and simply accept the added risk of dying at major events, which, after all, is not that much more significant than the risk of dying in a car accident on the way.
Obviously, that is not the response we'd expect, and it's not because Americans are irrational or fearful. It's because this prioritization-by-mortality-rate policy logic is faulty. It matters that there's an agency behind these deaths. One thing our society values highly is justice, and that often requires a disproportionately expensive response to an unjust act, and not solely to buy deterrence.