noun
smile diplomacy
A diplomatic approach that emphasizes friendliness, goodwill, and a pleasant demeanor to build relationships and resolve conflicts.
その国は微笑外交で近隣諸国との関係を改善しようとしている。
That country is trying to improve relations with its neighbors through smile diplomacy.
Compound of 微笑 (ほほえみ, 'smile') and 外交 (がいこう, 'diplomacy').