If the Japan-U.S. relationship has felt a little unstable in recent weeks, that’s understandable. Two of its pillars, Richard Armitage and Joseph S. Nye Jr., have died.

Those two men labored for decades to advance that partnership, working in academia, business and the policy-making worlds to protect and promote our two nations’ interests. Perhaps as no two other individuals have done, Nye and Armitage guided a bilateral relationship, creating a vision, using their knowledge, expertise and connections to bring it to life and then nurtured a generation of scholars, experts and officials who would give it substance and durability.

Joe Nye will probably be most remembered for conceptualizing the notion of “soft power,” the ability of a country to win the hearts and minds of others through its culture and values rather than coercion, but he worked and wrote on a variety of issues and topics. He and political scientist Robert Keohane are credited with founding the international relations theory of liberal institutionalism, which argues that cooperation between states is feasible and can reduce competition and is one of the two leading fields in that discipline.