The enhanced patdowns and full body scanners have been the subject of intense criticism from the public, citing privacy concerns.
The TSA announced last month the scanners will be phased out and replaced with more generic software, which auto-detects items that could pose a potential threat.
Pistole told the Newseum audience the TSA is moving to a more unpredictable approach to security than a one-size-fits-all approach.
“The terrorists keep adapting and evolving to try to defeat our security,” Pistole said. “The idea is that terrorists can’t go to school on what we do to try to beat us.”
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