OpenAI and Anthropic compete fiercely for customers. But in Washington, the two leading AI labs are aligning on one issue: warning policymakers about the risks of powerful Chinese open-weight AI models.Why it matters: That shared position pits the top U.S. AI labs against researchers, startups and open-model advocates who argue broad access to AI is essential for competition and scientific progress.The big picture: Closed-model labs stand to benefit from greater scrutiny of open-weight models. C...