In 2001, I was working as an airport screener. When I woke up on 9/11 and saw the news, I said to myself, “Wow. I hope that didn’t happen at my airport.”

I’m now a lead transportation security officer with the Transportation Security Administration. Ever since I’ve been here, my motto has been: This will never happen again, especially on my watch. I’m a former Marine, and I served in combat. I still have that sense of duty, like I did in Desert Storm.

This might be surprising to some people who have decided that the TSA is the worst. Only half of Americans surveyed in a 2014 poll said that TSA screening is making air travel safer. Headlines regularly denigrate our agency. (“Why are we spending $7 billion on the TSA?” “TSA, I think we have a problem.” “Abolish the TSA.”) The TSA is often the butt of jokes, and news of long security lines have been everywhere this summer.

But we’re not the evil force that you’re thinking of. We don’t get to argue the processes and procedures. I might not agree with every rule and policy, but I don’t get to make that call. We’re professionals, and we’re going to do our jobs – despite high stress and low pay.

Many vacation travelers who come through my security lines haven’t been to an airport for 20 years. All they see is the negative on TV, and they’ve got an expectation of an unpleasant experience. Then they get here and say, “That wasn’t bad at all!” The majority of people come through here and say “thank you” and “atta boy.”

The public would also be surprised to know how thorough we are and how much we catch: guns, knives, weapons. A couple of times they’ve had to evacuate the terminals and bring the bomb squad in to investigate.

It’s not easy. People come into the airport and say, “My flight’s leaving in five minutes.” We’re “encouraged” to do things to take short cuts. We’re told to hurry up and get a long line of people through security; often times, we can’t get a break until we get through that line.

And the public would be surprised by how poorly we’re treated. In a 2015 ranking of the best places to work in government, based on employee responses, the TSA took 313th place out of 320. Morale is rock bottom. We’re some of the lowest paid federal workers with some of the highest injury rates, and our work is very stressful.

As part of my job, I regularly meet new hires. On average, one person per new hire class is gone before they even get on the floor — less than two months after they start training. We have no outside protections.

But we take pride in what we do. And a lot of passengers seem to appreciate our work. Once, a huge group of Girl Scouts came through security; they were maybe 10 years old. Their leader counted to three, and they all yelled out “THANK YOU FOR KEEPING US SAFE.” And it was the most beautiful, touching thing. One of those is worth a thousand of the other people who don’t treat us well.

Vaughn Glenn is a TSA agent living in Detroit and wrote this guest commentary for the Washington Post.