Joseph S. Nye Jr., a Harvard University professor and former dean of the John F. Kennedy School of Government who died Tuesday at the age of 88, was known in Japan as a longtime advocate of stronger U.S.-Japan security ties centered on an expanded military alliance and a coauthor of reports that greatly influenced the direction of the bilateral relationship.

“Professor Nye possessed profound expertise on the Japan-U.S. alliance and made significant contributions to its strengthening through dialogue and policy recommendations,” Prime Minister Shigeru Ishiba said in an official statement of condolence Thursday.

Nye, who coined the term "soft power," or the use of nonmilitary means to persuade other nations, gained notice in Japan in 1995 when, as assistant secretary of defense under U.S. President Bill Clinton, he wrote the “Nye Report.” It echoed a 1993 Clinton administration report by calling for the continued presence of 100,000 troops in the Asia-Pacific region.