Internationalist (noun)

1. A person who supports or advocates for international cooperation and understanding.
2. A person who believes in the interconnectedness of nations and the importance of working together for the common good.
3. A person who actively works towards promoting and achieving international cooperation.

Origin:

From international + -ist.

Examples:

1. He was an internationalist who believed in the power of diplomacy to resolve conflicts.
2. She is an internationalist who works to promote peace and understanding between nations.
3. He is an internationalist who has dedicated his life to promoting cooperation and understanding among countries.
4. The internationalist movement has gained momentum in recent years.
5. As an internationalist, he was committed to the idea that all countries are interconnected and should work together for the common good.