The first in-person meeting between Xi Jinping and Joe Biden as presidents of their respective countries brought warm smiles but was low on deliverables.Biden said he doesn't expect an imminent Chinese attempt to invade Taiwan — which remains China's "red line" in its relations with the US.Elsewhere, climate cooperation could be revived, but there is little sign of China drifting away from its close ties to Russia. Save for later Print Download Share LinkedIn Twitter Xi and Biden's first face-to-face meeting seems proof that nothing beats in-person contact. Smiles, warm greetings and handshakes opened a meeting that lasted more than three hours. Respective readouts called for the two countries to "compete vigorously" (the US) and for "win-win cooperation" (China). The world appeared to sigh with relief at the thought that the US-China relationship had stepped back from the brink after US House Speaker Nancy’s Pelosi controversial visit to Taiwan this summer — and China’s subsequent aggressive military response. But the now more positive mood music shouldn't detract from the challenges ahead.