公共政策過程の実施主体は，実施対象からの信頼を獲得することが望ましい。しかし，主体に対する，あるいは主体間の信頼は，アプリオリに存在するわけではない。なぜなら立案主体，決定過程の参加主体と決定主体，実施主体それぞれの意思や調整をめぐる情報は，明示的なものであれ，黙示的なものであれ，完備情報化・完全情報化されないためである。さらに国際公共政策は，主権国家による外交政策決定過程を交えるため，一層のこと不完備・不完全情報の社会を対象にする。本稿ではトラスト（信頼）の先行研究を瞥見し，決定過程の完備情報・完全情報化を1つの理念型として想定する。その後，主体別（国内・国際）にトラストの構図を整理したうえで，完備情報社会に抗う複雑性・専門性と完全情報社会を浸食する時限性の要素を抽出し，国際・国内公共政策の決定過程におけるトラストのあり方について最後に提示する。

Arms control policy is aimed at achieving objectives such as (1) disarmament, (2) stability, and (3) the pursuit of superiority. These objectives can be understood as three aspects of arms control policy that are simultaneously in place, rather than mutually exclusive. Under stability, there was at the same time a technological and political competition between the great powers for superiority within a framework set by the arms control regime. Which of these aspects is emphasized in the negotiation and policy pursuits of arms control and which of these aspects comes into play in reaching an agreement between the parties will depend on (1) the international political environment, particularly the distribution of power, (2) domestic political dynamics, and (3) innovations in weapons technology.

This paper discusses how the multi-polarization of the international political structure due to the rise of China and changes in military strategy due to emerging technologies such as artificial intelligence, hypersonic gliding and precision warheads, missile defense, and cyber offense will affect the designing of deterrence architecture and the modality of nuclear arms control regime that defines the framework for strategic competition between the major powers.

The nuclear arms control regime encompasses the conflicting objectives of ensuring stability and pursuing superiority. As the United States, Russia, and China have different strategic visions and different prospects for power distribution in the future, which increase uncertainty in the prospect nature and modality of mutual relationships among them, as emerging technologies assign a strategic role to conventional and cyber technologies, and as non-strategic uses of nuclear weapons are incorporated into national nuclear policies, a concept of strategic stability will require extensive work to re-define. Institutionalizing nuclear deterrence at the strategic level based on mutual vulnerability is not enough to ensure stability among states, and the potential for intense security competition to unfold across the borders of nuclear, conventional and sub-conventional domains is increasing. As a result, different nuclear weapons employment policies make it difficult to find a point of equilibrium in the institutional design of an arms control regime that ensures the establishment of stability among the three countries, including the United States, Russia and China. In addition, as a result of the convergence of competition at the global level of the great powers and regional security that includes non-nuclear allies, a new challenge has also arisen: how can arms control bridge the stability at the strategic level between the great powers and security at the regional level?