The End of the Foundation Model Era: Open-Weight Models, Sovereign AI, and Inference as Infrastructure

TL;DR

The paper argues that the era of foundation models is ending, with open-weight models enabling sovereign control and a shift towards post-training optimization, driven by economic, technical, commercial, and political disruptions.

Contribution

It presents a comprehensive analysis of the structural shift in AI, highlighting the rise of open-weight models as instruments of sovereign control and the end of the foundation model era.

Findings

Open source models now achieve frontier performance.

Inference costs are approaching zero.

Open-weight models enable governments to exercise sovereign control.

Abstract

The foundation model era -- roughly 2020 to 2025 -- is over. The forces that defined it have inverted. Open source models have reached frontier performance while inference costs approach zero, exposing what was always structurally true: pre-training large language models at scale is not a durable competitive moat. The US government's formal designation of Anthropic as a supply chain risk in February 2026 accelerated a transition already underway -- but did not cause it. The paper argues that the AI industry is restructuring simultaneously along four axes: economic, as the circular financing structure that inflated foundation model valuations collapses; technical, as the pre-training scaling paradigm gives way to post-training optimization and agentic composition; commercial, as application-layer integrators displace the foundation model companies whose commodity they now consume; and political, as the government asserts its historic role as gatekeeper of strategic technology. These are not separate disruptions. They are one structural shift, arriving together. The paper further argues that open-weight models are the counterintuitive instrument of sovereign control: a government that holds the weights commands the capability on its own terms, without dependence on vendor policy, financial continuity, or personnel clearance.