Listen to TSA chief John S. Pistole for a few minutes, and you might feel guilty for ever grousing about a serpentine security line at the airport. The 26-year FBI man can widen your eyes talking about the latest destructive measures being invented by terrorists such as Ibrahim al-Asiri, the al-Qaida bombmaker accused of constructing the underwear explosives used in the botched suicide bombing of a Northwest Airlines flight over Detroit at Christmas 2009.

Yet Pistole, 57, is also sensitive to the many complaints about TSA tactics. You know, the police-state charade that repeatedly puts law-abiding Americans through a “Simon Says” security wringer before they can catch a flight to grandma’s house. He’s trying to change negative impressions of the agency by changing the agency itself. “We have undertaken some fairly significant changes both in policy and in procedures,” he says, “so more and more people are experiencing a different TSA at the airport.”

The agency is moving from what Pistole calls “a one-size-fits all approach” — where everyone is a potential terrorist — to “a risk-based intelligence-driven” system, where people with passive travel histories are expedited through security. This is being done through TSA PreCheck. The program began in October 2011 with Hartsfield-Jackson International Airport as one of the first four eligible gateways. PreCheck is in 40 airports now, a number expected to double by the end of year.

Basically, travelers can get security pre-clearance by enrolling through participating airlines — including Atlanta-based Delta — or in U.S. Customs and Border Protection trusted-traveler programs such as Global Entry. For information, go to: www.tsa.gov/tsa-precheck/how-participate.

After being approved, passengers can use a dedicated lane at airports. This should make things faster for everyone, in theory, because it lightens the load in the regular security line. Says Pistole: “You keep your shoes on, you keep your belt on, keep your light jacket on, keep your small-sized liquids and your laptop in your carry-on bag — you don’t even have to take those out — and then you go through a walk-through metal detector. We’ve done pre-screening of you.

“We’ve had about 45 million children, 12 and under, who have gone under expedited physical screening. It helps us in terms of expediting the time it takes to screen, especially for the elderly. We’ve probably had 25 million people, 75 and older, who are allowed to keep their shoes on; it’s all based on what past and current intelligence informs us of. If you haven’t been through TSA PreCheck, yet I strongly encourage you to sign up.”

The agency expects a big bump in users this fall when passengers can apply for enrollment directly through TSA — at a cost of $85 for five years. For information: www.tsa.gov/tsa-precheck/tsa-precheck-application-process.

Unfortunately, due to budget cuts, TSA cannot add personnel to handle the new influx, so your wait may feel like a familiar one, no matter what lane you’re in.

John S. Pistole is administrator of the Transportation Security Administration.