I have a French friend who would frequently mock Americans for being so "selfish".

Mindles H. Dreck and More than Zero both have posts regarding U.S. official and private giving. Highlights follow...

Concerning official giving:

When criticizing the percentage of national income given as aid, let's not lose sight of the actual amounts. The United States still gives out almost twice as much official aid as countries like France, Germany and the United Kingdom.

Concerning private aid:

Leonard Dickens dug up a recent analysis of the (2000) ratio of private and official aid [PDF document] and posted it in the comments thread Jane Galt's site . Yup, U.S. is tops. Only Ireland is in the same ballpark (see page 26 of the link).

Concerning French giving:

Net private aid from France is almost non-existent.

My own theory is that this is owed to a good economy, comparatively low tax rates, and deeply-held values. This jives well with Ireland's good showing too.