The topic of airport security tends to bring out strong opinions on both sides.

The Transportation Security Administration (TSA), the federal agency tasked with keeping the flying public safe, is bemoaned by critics as a bureaucratic mess. On the other hand, supporters say the federal agency, founded in the wake of the Sept. 11, 2001, terrorist attacks, is necessary to ensure the flying public remains safe.

To TSA Administrator John Pistole, the nation’s airport security measures stand as the “gold standard.”

“We know from intelligence that terrorists see the U.S. as the gold standard of aviation security, because of all the layers,” The Street quoted Pistole, a 26-year FBI veteran, as saying.

In remarks he made earlier this month to the United States Conference of Mayors, Pistole laid out a series of successes in thwarting terrorist attacks since 2001, including the 2001 shoe bomber, the 2009 Christmas attack and the 2010 Yemen cargo plot.

“When you consider the significance of transportation, and in particular aviation, to the strength and vitality of the global economy, the importance of securing every passenger, every bag and every piece of cargo cannot be overstated,” Pistole told the crowd.

“Early on, we focused on building and strengthening a layered approach to transportation security,” Pistole added. “We trained pilots and flight crews in self-defense, hardened all cockpit doors against unauthorized entry, and now screen 100 percent of domestic air cargo.”

The TSA, Pistole said, relies on “layers of security” to keep travelers safe. The positive news, is “there is no known or credible intelligence indicating an attack is imminent,” Pistole told the group.

But policy and political wonks might be interested in another tidbit Pistole shared with the group about the agency’s “greatest concern.”

“Our greatest concern is not necessarily with those on a no-fly list, those with some known affiliation or association with terrorist organizations,” Pistole said. “We know they warrant greater scrutiny and screening when and if they attempt to fly.

“Instead, it’s the radicalized individual who has somehow acquired the skill and ability to build an improvised explosive device and try to bring it onboard an aircraft, whether in checked or carry-on baggage,” Pistole added. “That’s why intelligence is critical, why collaboration at every level of government is essential, and why our role as one piece of a broader national security spectrum must remain strong. We know the stakes are too high to fail.”