A Republican congressman wants to know why U.S. airports remain vulnerable to terror attacks nearly a decade after 9/11 and despite billions spent to enhance security, and he's holding a hearing Wednesday, July 13, to find out.

Rep. Jason Chaffetz of Utah says U.S. airports have sustained more than 25,000 security breaches since November 2001. That averages to slightly more than five security breaches a year at each of the 457 commercial airports.

Chaffetz says the number of security breaches is "stunningly high," but a spokesman for the Transportation Security Administration says the number is a "tiny fraction of 1 percent" of the more than 5.5 billion travelers screened since 9/11, AP reported.