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war of aggression; war of conquest
侵略戦争は国際法で禁じられている。
Wars of aggression are prohibited under international law.
歴史の授業で侵略戦争の悲惨さを学んだ。
In history class, I learned about the horrors of wars of aggression.
侵略戦争を起こした国は国際社会から強く非難された。
Countries that launched wars of aggression were strongly condemned by the international community.