Does this video show that the members of the supposed Japan-U.S. Joint Committee are all American? No, that's not true: The footage used in the video comes from a Japan-U.S. security study group under the Sasakawa Peace Foundation, a nonprofit that has no consultative authority over Japan-U.S. relations.
The claim appeared on TikTok (archived here) on June 14, 2023. The video shows a press conference with American professors, with the caption (translated from Japanese into English by Lead Stories staff):
The current members of the Japan-US Joint Committee!
This is what the post looked like on TikTok at the time of writing:
(Source: TikTok screenshot taken on Tue Jun 27 02:18:47 2023 UTC)
The footage used in the video is actually a study group hosted by the Sasakawa Peace Foundation (SPF), Ministry of Foreign Affairs (MOFA) and the Center for Strategic and International Studies (CSIS) to study the future of Japan-U.S. security relations. The report and its creators are not an authoritative or consultive body unlike the Japan-U.S. Joint Committee's consultative position in Japan-U.S. affairs. The report remains an academic piece of text that may be used by policymakers for consultation and guidance.
The study group is made up of five American professors of political science and Japan studies and six Japanese government ministers and officials.