1.85% of GDP is US private charitable giving, 38% higher than any other nation. Your assertion that America needs to catch up with the rest of the world is, at best, xenophobic.
You need to factor in the amount of tax that other developed countries pay to look after their own citizens..things like heath care, welfare, higher education, etc., then see how the US compares.
I don't have numbers, but after living and paying tax in Australia, Canada and the US, I'm willing to bet Americans pay less than those from other Developed countries.