Historical note: Lend Lease Act,

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The bill was initiated in the House of Representatives on January 10, 1941. America was not yet in the war but Roosevelt knew it was coming.
The act prompted the following remark from British Prime Minister Winston Churchill:

Then came the majestic policy of the President and Congress of the United States in passing the Lease-Lend Bill, under which, in two successive enactments, about £3,000,000,000 was dedicated to the cause of world freedom, without -- mark this, because it is unique -- without the setting up of any account in money. Never again let us hear the taunt that money is the ruling power in the hearts and thoughts of the American democracy. The Lease-Lend Bill must be regarded without question as the most unsordid act in the whole of recorded history.

notes: The exchange rate was 1£ = 4$ which meant that the amount was $12 billion. The total GDP (GNP in those days) for the US was about $100 billion per year. That is we gave them 12% of our yearly income. A corresponding amount today would be about $1,800 billion or $1.8 trillion.
I am sure that those who ridicule the notion of American Exceptionalism will supply us a few comparable acts by other nations.
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