Apart from it just being morally and ethically righteous for rich countries to share their wealth globally, American "soft power" serves as a gesture of good will to the world so they will tolerate a strong dollar (so we get to play global economics on easy mode) and American hegemony generally. When we stop exercising "soft power" everyone will just resent our relative comfort and suddenly decide they aren't okay with us being on the throne anymore. And we'll find ourselves playing on hard mode because we'll be iced out from global trade.
Is it morally and ethically righteous toward the people of the rich countries? A country owes everything to its citizens and nothing to anyone else, and pretending otherwise led to resentment toward foreign aid including some realpolitik justified programs like USAID. When programs are sold to the people as being selfless while people are less fortunate than the social media influencers they watch every day, it’s only natural that they resent the government for seemingly giving resources away.
