Frank Masson is the Secretary of Defense under President David Bowers during the events of Chaos Theory. In response to North Korea and China's blockade of Japan, Mason sent the USS Clarence E. Walsh to the Yellow Sea to reaffirm the US commitments to Japan. After both Japan and the eastern United States fell victim to an information warfare attack and blackout, Mason began suspecting the Koreans. After the Walsh was sunk by a Korean missile, Mason tried to push Bowers to declare war immediately, before Lambert gives more intelligence.
Mason uses a very hardline approach when dealing with problems. While he encouraged the President to send out troops (and, at one point, to use nuclear devices to stop the Korea conflict), Lambert managed to talk him down, preventing a terrible crisis. Near the end of the crises, Mason agrees with Lambert to take out Shetland (whose company had contracts with United States government), and capture Otomo.