Stanley Baldwin, a leading British conservative of the early 20th Century and three-term Prime Minister, understood far earlier and better than his contemporaries how industrialization was changing the nature of war and conflict. The new development of the inter-War era, of course, was the airplane. Aviation moved the battlefield away from trenches and into cities. It de-compartmentalized nations, blurring the distinction between civilian and military and allowing for the first time the prospect of total war and the potential for total defeat. With the power to level cities and turn entire nations into rubble, aviation ensured that nations, not armies, would be defeated in future wars.

Baldwin understood this, and World War II was a graphic example of the ability of air power to turn defeat into total destruction. Accordingly, nations preoccupied themselves during the inter-War era with devising ways to defend against aerial bombing. France, Britain, Russia, Germany, and the other European nations with a millennium-long history of starting wars with one another every decade or so concocted intricate and expensive schemes to defend their skies. It was all folly, Baldwin warned. People should not develop a false sense of security based on military might and seemingly impregnable defenses. "I think it is well also for the man in the street to realize that there is no power on earth that can protect him from being bombed. Whatever people may tell him, the bomber will always get through." No matter how extensive the preparations or how fearsome one's military might be, enough of an attacking force will survive to inflict significant damage.

The PM's saying was relevant throughout the Cold War – didn't someone make perhaps the greatest film of all time about this very problem? – and it is even more so today despite the rapid obsolescence of nation-state conflicts. I thought about the Rt. Hon. Mr. Baldwin's words extensively on Christmas Day, the day on which, despite the dramatic increase in airport security since 2001, yet another person managed to carry an explosive on an airplane and come perilously close to using it for its intended purpose.

The reaction to the attempted bombing of Northwest Flight 253 has been predictably stupid – public shaming of the TSA (despite the fact that the flight originated far outside TSA jurisdiction), idiotic partisan fingerpointing (apparently this would never have happened if Bush was President, or Obama deserves blame for the failure of security policies instituted by his predecessor), and pointless speculation. Useless, all of it. The facts about airport security, like border security or air defenses, are deceptively simple. Someone will always get through.

I certainly think that airport security could be improved, and ironically I posted on the TSA's laziness on the morning of the incident. But let's not kid ourselves. All the metal detectors and X-ray machines and explosives detection equipment on the world won't stop people who want to blow up airplanes from blowing up airplanes. This is not to say that security is futile; certainly it can reduce the number of incidents. What it does very well is catch the complete knuckleheads – people with guns in their carry-ons or laughably bad fake identification. You know as well as I do, however, that someone with reasonable intelligence who commits him- or herself to the goal of blowing up an airplane can find a way to do it. No matter how good the security, people will find a way to defeat it. Maybe not a lot of people, but enough to spread the lingering fear that it can happen anytime. That's the goal of terrorism. That's why it's called "terrorism."

The gaps in our security are apparent to anyone who spends appreciable time in airports and cares to be observant while standing listlessly in a security checkpoint queue. But not even another dramatic improvement in security – "Total Body Imaging" scanners, for example – can eliminate the specter of terrorism. For the past eight years much of America has operated under the delusion that terrorism can be Defeated, that there will be a moment at which it stands on the deck of the USS Missouri and signs an instrument of surrender in deference to our military might. It is a pipe dream. There are six billion people on this planet and there is no way to prevent a small handful of them from deciding that it will be a good or useful idea to blow up a 747. And as long as the intent exists, that intent will occasionally intersect with means. I'm going to keep flying, as the odds of being on a plane when a terrorist blows it up are infinitely smaller than my chances of drowning in my bathtub (which are a comparatively terrifying 1 in 700,000). But while I'm at it I'll refrain from expecting airport security from stopping everyone or elected officials from magically "ending" terrorism. The bomber will always get through and punish someone – someone else, we all silently hope whenever we step on an airplane.