Transportation Security Administration employees subjected "Middle Easterners" to extra screening based solely on national origin, diverted "rude" passengers to retaliatory pat-down searches, and snickered at our "every fold and dimple on full awful display" from full-body scanners, according to former TSA employee Jason Edward Harrington. In a withering exposé entitled "Dear America, I Saw You Naked," Mr. Harrington draws back the curtain on the unfairness and absurdity of airport screening practices.

To the extent that any theme unifies Harrington's revelations, published in Politico today, it is that the TSA invades our privacy in ways that make us no more secure. The blanket selection of travelers holding passports from a list of certain countries for additional screening is a case in point. Citizens of the only non-Middle Eastern countries on the list (Cuba and North Korea) rarely travel to the United States, Harrington said, so the list amounts to a de facto policy of systematically profiling people of Middle Eastern origin. Mr. Harrington, whose father is African American, felt that he was "enabling the same government-sanctioned bigotry my father had fought so hard to escape."

Other disclosures follow the same pattern. The full-body scanners allowed TSA employees to gawk at, and joke about, explicit images of travelers' bodies from a locked room full of monitors. (The software program that the scanners used has since been replaced with one that shows only a generic outline of the human form.) According to Mr. Harrington, "all the old, crass stereotypes about race and genitalia size thrived on our secure government radio channels."

As with the discriminatory profiling, it appears that these intrusions on our privacy served no purpose. Mr. Harrington writes that "the scanners were useless" and would fail to detect a metal object concealed on the side of a passenger's body. Thus, the detectors "were good at detecting just about everything besides cleverly hidden explosives and guns."

Given what we already know about TSA practices, the revelations from Mr. Harrington are somehow jarring and unsurprising at the same time. They are sadly consistent with the use of blacklists to prevent unknown thousands from flying without any meaningful redress procedure, or the use of pseudo-scientific techniques by "behavior detection officers," who subjectively screen passengers based on what the officers perceive to be stress, fear, or deception.

The TSA serves an important purpose, and many of its employees surely approach their jobs more responsibly than those Mr. Harrington describes. But it seems clear that TSA policies actively foster racial, religious, and national origin profiling, untethered from any national security imperative. They also perpetuate a screening system that routinely subjects travelers to unnecessary, invasive searches. Need proof? Ask the TSA employees themselves: according to Mr. Harrington, "most TSA officers" he spoke with "felt the agency's day-to-day operations represented an abuse of public trust and funds."

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