Look at your fellow travelers the next time you’re in an airport security line. There’s a unique expression shared by most waiting to have their carry-on bags and persons scrutinized by Transportation Security Administration officers (TSA).

It’s a look best described as pained-yet-determined patience. No one enjoys putting toiletries in Ziploc bags and removing shoes, keys, coins and laptops in a rush to get them into plastic bins. No traveler, even if the luggage is Louis Vuitton, looks dignified trudging through the scanner in sockfeet. Yet we endure this with eyes straight ahead and lips pursed to suppress groans at slower, less experienced travelers because the payoff is public safety.

At least, that’s what we’ve been told. But this week, the leaked — and abysmal — results of test screenings by an undercover TSA team raises frustrating questions about what travelers are getting in return for their time and the investment of hundreds of millions of tax dollars into agency staffing and technology. Is the current airport screening process effective? Or is it merely “security theater,’’ as expert Bruce Schneier has dubbed it, that does relatively little but consumes so much energy that more evolved, effective safeguards fail to get due consideration?

Fourteen years after the Sept. 11 terrorist attacks, it’s time to ask these questions. The recent leak about TSA screenings ought to jump-start a national debate. Agents posing as passengers at various airports across the nation were able to sneak fake bombs or weapons past TSA officers almost every time they tried. According to ABC News, the undercover agents “succeeded” in 95 percent of test runs. One agent with a taped-on mock bomb wasn’t stopped after setting off a detection alarm and getting a pat-down. How does this happen?

It’s unclear which airports were involved in the testing. Department of Homeland Security officials declined to say if Minneapolis-St. Paul was one of them. Metropolitan Airports Commission officials in Minnesota referred information requests to Homeland Security.

The federal agency has apparently reassigned the head of airport screening to another internal job. But answers to other legitimate questions were not forthcoming: Was it a type of screening equipment that failed repeatedly? Do other checkpoints, such as those for low-level airport employees, have gaping weaknesses? Are agent hiring practices or training flawed?

The exercise’s test results are preliminary and classified, the agency said in a statement that also provided vague reassurances about improvements and “multiple layers of detection and protection.’’ But in 2013, there were similar assurances — and excuses — when an undercover agent wearing a fake bomb evaded TSA screeners. The situation obviously has not improved, which is why Homeland Security needs to provide more than the “nothing to see here, move along” statement that it has. The flying public also deserves an honest, clear-eyed assessment of whether current screening practices are delivering the protections we expect.