Happy Memorial Day! This past weekend is one of the year's busiest for air travelers, with the AAA forecasting that 2.6 million people will travel by plane sometime between Thursday and Monday, up from 2.4 million last year.

That means 2.6 million people will be reminded yet again of the unremitting awfulness of the TSA, which has been subjecting fliers to frisking, invasive body scans, (alleged) racial profiling, needless checking of liquids and nail clippers, and various other indignities for nearly thirteen years now.

It's worth remembering that the inconvenience and injustice of the TSA's activities exists for literally no reason. If the agency's privacy violations and annoying carry-on regulations were merely the price we paid for reducing the incidence of terrorist attacks, that'd be one thing. But, as security expert Bruce Schneier likes to note, there's no evidence that the TSA has ever prevented a terrorist attack, and there's some research suggesting it could serve to increase non-airborne terrorist attacks. Airline security is, so far as we can tell, totally useless.

A literature review by George Mason's Cynthia Lum and Rutgers' Leslie Kennedy and Alison Sherley shows that studies testing the effectiveness of airport security — specifically, of metal detectors and security screenings — found, on average, that the measures in question prevented about 6.3 hijackings over the years examined. If that were all they found, that'd be a pretty solid case for the TSA.

But the attacks weren't simply being prevented; they were being displaced. While there were 6.3 fewer hijackings, there were 6.8 more "miscellaneous bombings, armed attacks, hostage taking, and events which included death or wounded individuals (as opposed to non-casualty incidents) in both the short and long run." Making hijackings harder, in other words, didn't reduce attacks, but encouraged would-be hijackers to attack through other means. Additional research done after the review has similarly concluded that screenings are, in effect, a wash.

The literature base on counterterrorism efficacy is appallingly small, and it's always possible that future studies with better research design will conclude different things. But given the costs of the TSA — to the federal budget, to individual privacy, to the time of travelers, etc. — the fact that there's no empirical evidence suggesting that it accomplishes any of its intended goals is galling.

What to do, then? Simple: just abolish the agency. This is hardly an extreme proposal; members of Congress, including influential figures like Senator Rand Paul (R-Kentucky) and Congressman John Mica (R-Florida), have endorsed it. The Cato Institute's Chris Edwards wants to privatize the TSA and devolve its responsibilities to airports, but that preserves far too much of the status quo. Better would be to make security the responsibility of individual airlines, so as to allow competition on that dimension.

Some people, naturally, will value the security theater of screenings and metal scanning, just like Homer Simpson values having a rock to defend himself against tigers. So why not let them fly Bodyscan Airways while the rest of us fly airlines that don't include scans? You could imagine companies that own several different airline brands using this as a method of diversification. American Airlines could offer no-screening flights and US Airways screened flights, and the company that owns both services could enjoy the business of worrywarts and more relaxed fliers alike.