2022年2月，ロシアがウクライナに軍事侵攻し，ザポリージャ，チョルノービリ両原子力発電所を攻撃した。ザポリージャ原発については占拠を続けている。運転中の原発を武力攻撃し，占拠するのは前代未聞の出来事であり，従来の核セキュリティの概念を超越している。

　米国アルゴンヌ国立研究所の開発した高速炉と乾式サイクル施設を統合した統合型高速炉は受動的安全性，核不拡散性，放射性廃棄物の減容化において優れた核燃料サイクル方式である。またこのシステムは福島第一原子力発電所事故で生じた燃料デブリの処理に適用可能な技術と考えられる。実際にこの技術を使った場合，デブリ処理に要する時間，施設の安全性，建設コストを試算するとともに今後の技術的課題などの技術的可能性を検討した。

As a part of the Japan-U.S. Alliance, the Japan-U.S. Security Consultative Committee (SCC) is situated at the top of the hierarchical channel for security talks. The SCC played a major role in the management of the Japan-U.S. Alliance during the post-Cold War era as it was reorganized into a “2+2” meeting structure in which two foreign ministers and two defense ministers participate. However, there have been no studies that have tracked the historical changes in the talks system or the talks process.

This paper aims to track the historical transformations in the processes relating to how agreements are reached and to clarify the qualitative changes in these processes until the enactment of the “2+2” system. We will chronologically follow the historical transformations in the Japan-U.S. talks by focusing on the following two points: centered on the “2+2” meetings, how the consulted channels such as the Security Sub-Committee (SSC), the Mini-SSC, and the Sub-Committee on Defense Cooperation (SDC) were utilized in the process of strengthening the alliance; and how actors such as the politicians and the bureaucratic organizations in Japan and the United States spearheaded the agreement. The following became clear as a result of doing this.

In the 1990s, the “2+2” meetings became increasingly important as a type of ceremony that demonstrated the strengthening of an alliance. They also transitioned to being a forum in which each of the channels of consultation was converted into a group of processes. The “2+2” meetings then came to play the role of controlling the deadlines for the targets to be met in each of the consultation channels and the channels themselves. In addition, the meetings were positioned as a part of a “comprehensive mechanism” through which Japan and the United States formulated operational plans during emergencies and critical situations in the areas surrounding Japan.

In the 2000s, there was a change on the Japanese side, whereby the agreement process changed from being led by the Ministry of Foreign Affairs to being led by the Prime Minister’s Office. This strengthened the initiative of the cabinet ministers and expanded the role of the Ministry of Defense, in particular the uniformed members of the armed forces. As a result, the negotiations with the United States were held in the form of a joint team for foreign affairs and defense under the Prime Minister’s Office, allowing them to deal with the political issues that were difficult to coordinate. In addition, the uniformed personnel group within the Self-Defense Force (SDF) made use of it expertise to realign the bases as well as the units of the SDF and U.S. forces in Japan, thereby strengthening the military cooperation.

In the 2010’s, the Japanese side proposed a revision of the 1997 Guidelines for Japan-U.S. Defense Cooperation along with the consideration and coordination of the expansion of the Japan-U.S. roles, including the partial acceptance of the right to have a collective self-defense.

It became clear that the qualitative changes in the “2+2” system as described above had gradually strengthened the framework of the Japan-U.S. Alliance. While “2+2” did not fully function right from the beginning, nevertheless, through the changes in the situation in East Asia post the end of Cold War and other factors, the two countries accumulated an experience of more than 20 years and qualitatively shifted towards more politically, militarily, and pragmatically important engagements.

気候変動対策として温室効果ガス排出の抑制と再生可能なエネルギー供給の推進に向け、我が国では2018 年に再エネ海域利用法が制定された。洋上風力発電の事業化支援に向け、洋上空間の長期占有が認められ、指定された推進区域では協議会を通じて利害調整が進められている。本研究では、文献調査や聞き取りを通じて、洋上風力発電に関連するステークホルダーの利害関係の構図化とその分析を行った。ステークホルダーの多様性に対し、法規上の協議会の構成は限定的で包摂性が乏しいと考えられた。民間企業としての分類される事業者の利害は一様ではなく、製造、組立、施行、管理、投融資など多様な事業形態があり、本社や株主の所在地なども多様でありうることが分かった。こうした多様性に留意したステークホルダー分析を踏まえ、参加型合意形成と持続可能な海洋経済を通じた地域社会の利益の増進に資する制度的発展を進めることが肝要である。