Biden tests political climate at home and abroad: The Note Biden and Harris speak on Derek Chauvin verdict Replay Video It's a grand moment for global leadership -- assuming the audiences at home and abroad are looking for it. President Joe Biden faces perhaps his biggest test yet on the international stage with the two-day climate summit that begins on Thursday, a mostly virtual gathering organized by the White House to coincide with Earth Day. Biden's message to the world is a reassertion of American leadership to address climate change. He faces expected skepticism from familiar corners -- China, Russia and swaths of the developing world -- with the European Union jostling for primacy, and scrutiny on U.S. allies including Canada and Japan.