President Donald Trump and Chinese President Xi Jinping are preparing for their first in-person meeting during Trump’s second administration, a high-stakes moment in the diplomatic battle for superpower supremacy.

Their sit-down on Thursday in Busan, South Korea, on the sidelines of this year’s Asia-Pacific Economic Cooperation leaders summit, comes as the United States and China are locked in a bitter trade war, with triple-digit tariff rates and a race for control over rare earth elements. That’s not to mention the Taiwan-sized elephant in the room, the Russian threat, and nuclear arms control.