Raizo Yamata's family jumped from a cliff to its death rather than endure capture by the barbaric Americans in 1944. Before the war, life was good on the island of Saipan, where his father supported the family as a minor merchant. When America occupied the Mariana Islands, moreover, Yamata remained in Japan with grandparents and is now a wealthy entrepreneur with a great deal of influence among his peers and the opposition party in the Japanese Diet. Yamata has always hated America, is obsessed with plotting revenge, and has developed a plan to accomplish this while building the Japanese Empire that should have been the result of World War II. This is his debt of honor both to his family and to his country. Yamata has been patient, waiting for the correct alignment of circumstances, to put his plan into action.

As the United States and Russia disarm in a new epoch of peace, Yamata secretly builds nuclear ICBM's, manages to place his puppet in the position of Prime Minister, and occupies the Marianas. At the same time, he throws the U.S. economy into crisis through computer espionage and develops treacherous alliances with China and India. The ultimate goal is the invasion of Siberia, for its resource wealth and, of course, a Japanese empire in Asia. China and Japan are to share in Siberian wealth and India can begin its empire in South Asia by the invasion and occupation of Sri Lanka.

Disarmed and with significantly reduced military forces, the United States and Russia are not in a position to defeat Japan militarily. They must rely upon intelligence gathering, attacks on a few key targets, and political maneuvering, as a part of an overall plan developed by newly appointed National Security Adviser, Jack Ryan and friend Admiral Rob Jackson. This is the new warfare, Ryan realizes, in an era of global economics, high tech espionage and stealth tactics.

Operation Zorro involves disarming Japan's air defense system, landing rangers in the wilderness, destroying missile silo sites, killing off the zaibatsu who follow Zapata, and using CIA and KGB operators to confuse and disrupt the treacherous government and business leaders of that country. Killing is involved, of course, but it will not be the total conventional warfare that pits one soldier against another or that annihilates entire populations through nuclear holocaust.

Through a continual jockeying among several individual segments of Operation Zorro, Clancy is able to bring the reader to the climaxes and denouements, only to deliver the additional punch of a shock kamikaze attack on the Capitol as all government officials are attending Jack Ryan's swearing in as Vice-President. In a matter of moments, Ryan is catapulted to the Presidency, a position he does not want but will assume nevertheless, as a part of his debt of honor.