Joe Biden and Xi Jinping represent two worlds that many consider to be on a collision course. Biden is set to hold his first in person meeting with Xi on the sidelines of the G20 summit, where leaders come together to find common ground.But a meeting of the minds is unlikely and not necessarily in the national security interests of the United States, according to the commmander of US Strategic Command, Navy Admiral Charles Richard. In a recent speech the adminral called for a fundamental change in the way the US thinks about its own defense. He says the Ukraine crisis is just a warmup, and that the big conflict is the one coming with China.