The difference is....unlike charitable giving, which is what Jesus advocated....what the president and the pope are pushing is extortion based on manufactured guilt (over being wealthy, successful, thriving, etc. as a nation). And that is anything BUT charity. It's just the usual leftist meme of punishing success at the expense of the failed. And a blatant robbing of capitalist nations, of course.
For instance, how much $$$ is China going to be expected to fork over? Zilch, I'm betting...since they aren't even expected to curb their massive and ongoing pollution. The game is fixed/rigged.
The Chinese will have the same contribution on international global warming as they have on the refugee crisis.