JD Vance held an ad-hoc AI safety summit last month, gathering a conference call with the nation’s top tech CEOs after a new Anthropic model showed how easily it could autonomously find, and then exploit, the types of cybersecurity systems that guard against attacks on banks, hospitals, infrastructure and just about anything else. The April phone call included Elon Musk, OpenAI CEO Sam Altman, Google CEO Sundar Pichai, Microsoft CEO Satya Nadell…