What are the reasons why united State provides foreign aid to other countries?

as a 1rst world country the us states along with other countries are made by the United Nations to "keep peace" and help other counties in need
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Do any countries other than the United States have President's give a State of the Union address?

Why is providing humanitarian aid to foreign countries a useful part of US foreign policy?

The US offers foreign aid MOSTLY to support struggling democracies and countries that are critical to foreign policy objectives True Or False?

Is it illegal to fight for other countries at war this is about private citizens of one country getting involved for no fee to assist the fighting efforts of other countries at a state of civil war?