The largest artificial intelligence (AI) firms increasingly understand that they are hostages of one another. If one firm pushes ahead recklessly, others may feel compelled to follow. If one deploys a dangerous model without adequate safeguards, others may see it as a green light to do the same. The debate over AI has centered on what governments should do to regulate this frontier technology. That remains essential. But a more immediate question is emerging: Can the companies building these powerful systems take action independently before they lose credibility and suffer legal consequences? That question no longer looks theoretical and is being recognized as an urgent challenge. We've alre...