text: Calling the September 11, 2001, attacks an act of "air piracy", Paul introduced the Marque and Reprisal Act of 2001. Letters of marque and reprisal, authorized by article I, section 8 of the Constitution, would have targeted specific terrorist suspects instead of invoking war against a foreign state. Paul reintroduced this legislation as the Marque and Reprisal Act of 2007. He voted with the majority for the original Authorization for Use of Military Force Against Terrorists in Afghanistan. In April 2009, following the Maersk Alabama hijacking, he proposed issuing letters of marque to combat the problem of piracy in Somalia.
  Airport security
  Following the 9/11 attacks, Paul "opposed the federalization of airport security, the creation of the DHS and increased police state measures, but did propose legislation that would allow airline pilots to begin carrying firearms in cockpits", on the rationale that "it's much harder for terrorists to commandeer an airplane when pilots can fight back."
  Investigation
  Paul supports reopening investigation into the attacks to discover why the Federal Bureau of Investigation did not act on 70 internal field tips: "We had one FBI agent, I think sent dozens and dozens of memos to his superiors saying that there are people trying to fly airplanes but not land them, and nobody would pay any attention." He also advocates investigating why the various intelligence agencies could not collaborate on information to prevent the attacks while spending $40 billion per year. He has called the 9/11 Commission Report a "charade", saying "spending more money abroad or restricting liberties at home will do nothing to deter terrorists, yet this is exactly what the 9–11 Commission recommends."
  Rejection of 9/11 conspiracy theory