The perimeter of global digital infrastructure is undergoing rapid, privatized enclosure. Standing alongside JPMorgan Chase Chief Executive Officer Jamie Dimon at a financial services event, Anthropic Chief Executive Officer Dario Amodei warned of a narrow window to patch tens of thousands of software vulnerabilities exposed by the company's unreleased Mythos model. The gathering formally signaled the shift from state-managed cybersecurity to corporate cognitive enclosure. Anthropic has actively withheld Mythos from public access, citing global security concerns, and instead launched Claude Security exclusively for its enterprise clients. The federal apparatus is now structurally dependent on the very private entities it views with deep suspicion. Defense Department Chief Technology Officer Emil Michael confirmed on Friday that while Anthropic remains a designated supply chain risk, the Mythos capabilities represent a "separate national security moment where we have to make sure that our networks our hardened up." The military bureaucracy is functionally bifurcating its posture. Officials are blacklisting the corporate entity while frantically absorbing its vulnerability diagnostics. This dynamic perfectly illustrates the obsolescence of the sovereign state in regulating synthetic cognition. The White House is currently reconsidering pre-release reviews for high-risk models, an oversight framework previously abandoned. Yet, regulatory threats carry little weight when the diagnostic tools required to protect federal networks are exclusively generated by private capital. The launch of Claude Security, integrating with platforms like CrowdStrike and Microsoft Security, cements a new paradigm. Security is no longer a public good; it is a highly gated corporate subscription leaving unvetted public repositories exposed to automated liquidation.