We (the US) didn't have a tenth of the security that we have today... things have been going all wrong.
We don't have a tenth of the security that people
think we do. Much of what you see is mostly to reassure the public, not necessarily have the greatest impact. Port security is still a joke, cargo/freight security is still a total crapshoot when it comes to nailing contraband/weapons, critical site physical security still has major gaps, border security is still pretty much Swiss cheese, and cyber-security honestly keeps me awake some nights, because if the shit's really gonna go down, that's going to be the attack vector.
But hey, airplanes are pretty safe now.
Mind you, I'm not saying we need to be Fortress America. I'm saying that Fortress America is an impossible goal, but it's one that's still politically (and for some, financially) advantageous to tout.
EDIT: @Virex, the problem with that is that it's counter to what is supposed to be the American ideal of justice: Presumption of innocence and the notion that it's better that 50 guilty men go free than one innocent man to suffer unjustly. Instead we've taken to adopting what we used to consider the "inferior" form of justice in which you round up everybody and punish them all, because at least you're likely to get some guilty ones in there. You know, the Royal version of justice that prompted us to write the Bill of Rights in the first place.
Meanwhile, we treat someone as a dangerous threat for having the temerity to be brown-skinned and on an airplane, but continue to treat major financial crimes as misdemeanors or even just as "poor business decisions". Maybe we need to get more Arabs in CEO positions, then they'll start cracking down. (And yes, I'm being a cynical ass.)