Pentagon continues implementing AI into military forces by bringing on OpenAI

The US Department of War is continuing with the expansion of its GenAI.mil platform that facilitates the use of AI by military personnel as OpenAI’s ChatGPT is joining Grok from Elon Musk’s xAI and Gemini developed by Google on the project.

US War Secretary Pete Hegseth and Pentagon CTO Emil Michael officially launched the platform two months ago, aiming to provide large language model tools to roughly three million uniformed personnel, civilian employees and contractors across the department. GenAI.mil now reports 1.1 million unique users, with officials saying the system has experienced no downtime or significant technical issues since its debut, as reported by military news outlets.

All three military service branches within the Defense Department — the Departments of the Army, the Navy and the Air Force (including the Space Force) — have announced their adoption of the platform. In a post referencing Grok, the Air Force said it is “phasing out legacy AI systems” that were used in earlier efforts to integrate commercial models.

In a press release, OpenAI described earlier this month that the deployment as “a custom version of ChatGPT [that] runs in authorized government cloud infrastructure with built-in safety controls and protections for the Department’s highly sensitive data.”

“Data processed on GenAI.mil remains isolated to the government environment and is not used to train or improve OpenAI’s public or commercial models, ensuring separation from external systems and protecting mission data," the company added.

Offering multiple AI systems was part of the original strategy. The platform initially launched with Google’s Gemini, added Grok shortly before Christmas 2025, and is now rolling out ChatGPT — the generative AI system that helped spark the current wave of AI adoption three years ago. The versions deployed on GenAI.mil are modified from their public counterparts and cleared for use with sensitive but unclassified information. Authorization for handling “secret” or “top secret” data remains a significantly higher threshold.

The War Department’s use of ChatGPT stems from OpenAI for Government, an initiative launched in June after the Pentagon’s Chief Digital and AI Officer awarded OpenAI a contract worth up to $200 million. Similar contracts — also valued at up to $200 million — were later issued to xAI, Google and Anthropic.

Of the four leading “frontier” AI models that received awards last summer, only Claude, developed by Anthropic, is not yet available on GenAI.mil. Industry observers note that if the platform continues to expand, Claude could be a future addition.

By Nazrin Sadigova