noun
open diplomacy
Diplomacy conducted with public observation and transparency, often contrasted with secret diplomacy.
公開外交は、国民の信頼を得るために重要だ。
Open diplomacy is important for gaining public trust.
秘密外交 means secret diplomacy, the opposite of 公開外交.
Compound of 公開 (open, public) and 外交 (diplomacy).