Korea's president came to America last month and made only one stop: Silicon Valley. a16z's @jkhamehl explains what that says about the new geopolitics of AI: "A month ago, the president of Korea came to the US, and their first and only stop in the US was in Silicon Valley. Which is really interesting, right?" "NVIDIA at 5.5 trillion is the same size as countries in terms of their GDP. NVIDIA's larger than all of the G7 countries except the US. That scale is just totally different. Our…