Humiliating. The proper response is "Yes, that is our position - we support our allies. If you don't like it, there is the door. Leave. But if you walk away you will trigger a trade war and your people will starve. Think carefully about what you are willing to do. Or sit down, and we can have a discussion, but if you come to insult us you can leave."

Ambassadors under biden are gutless. Trump never would have tolerated this shit, and would have shut this meeting down instantly. China knows they own Biden (and his son) so they can twist his balls and he will smile.