The Pentagon is building AI data centres on its own land, and Congress has been trying to stop it from three directions — two of them in the past week. Two of those efforts are loud, well-endorsed and going nowhere. The third has already passed the House, has drawn a fraction of the coverage, and the Army is the one objecting to it.

What is actually being built

The Army has selected the Carlyle Group to build a large data centre at Fort Bliss in Texas — expected to reach initial operating capability in fiscal 2027 — and CyrusOne, jointly owned by KKR and BlackRock, to develop a similar project at Dugway Proving Ground in Utah. It is not only the Army: the Air Force is opening unused land across five bases to private companies for the same purpose.

That is the thing all three congressional efforts are aimed at. They are aimed very differently.

The one that landed

Rep. Cory Mills (R-Fla.) got a provision into the House Armed Services Committee's version of the fiscal 2027 National Defense Authorization Act. It bars the Defense Department from leasing its land to private companies for data centres unless those companies agree not to install or operate equipment containing components manufactured in China, Russia, Iran or North Korea — certain printed circuit boards, advanced semiconductors, chipsets and other parts the department deems a national security risk.

It is a supply-chain objection rather than an environmental or an AI one: the argument that hardware sitting on a military installation and processing military data should not contain parts made by the countries that installation exists to deter.

It rode the NDAA — H.R. 8800, the one piece of must-pass legislation in this fight — through the House on 22 July, by 216 votes to 212.

The Army's objection is worth reading closely, because it is not the objection you would expect. It says the measure sets an "unworkable standard" that would "drive world-class commercial partners — and over $1.3 billion in private capital — away from Army land," creating what it calls a "federal land penalty": requirements on companies building on military installations that would not apply to the identical facility built on private land a mile away. Its stated reasoning is about supply, not standards — that the domestic industrial base does not yet make some of the equipment data centres need — and it argues commercial operators on federal land "already fall under strict, existing federal security requirements."

So the dispute is not really about whether adversary components belong on a base. It is about whether a rule that applies only inside the fence will simply push the buildout outside it.

The two that did not

On 23 July, Rep. Rashida Tlaib (D-MI-12) introduced the No AI Data Centers on Federal Lands Act — H.R. 9939 — which would permanently ban large AI data centres and associated infrastructure on land owned or managed by the United States, military bases explicitly included. According to her office it would go further than any of the others by requiring the removal of existing qualifying AI data centres and mandating site remediation; the bill text has not yet been published, so that characterisation is hers.

Tlaib's framing is environmental and economic rather than strategic: "AI data centers bring noise, light, air, and water pollution," she said, and, later in the same statement, that "our corrupt, AI-addicted President cannot be allowed to sacrifice our federal lands so that Big Tech oligarchs can get richer." Her release states that the Department of Defense requested $30 billion to build hyperscale data centres, that the Bureau of Land Management recently approved the first data centre on BLM land in Nevada without public input, and that such facilities could be built without Clean Air Act permits under a new rule revoking environmental protections. Those are her office's characterisations, not independently established here.

The bill is co-sponsored by Jim McGovern, Adelita Grijalva, Delia Ramirez, Mark Pocan and Bonnie Watson Coleman, and endorsed by the Center for Biological Diversity, Climate Justice Alliance, Food & Water Watch and Win Without War. It was referred to the House Committee on Natural Resources the day it was introduced.

Win Without War's deputy director, Shayna Lewis, put the militarised version of the argument most directly: public lands "should not be turned into sacrifice zones for the AI arms race," and the bill would protect communities from shouldering the costs of "systems designed to accelerate war-making and deepen the Pentagon's deference to Big Tech."

The third effort is older. On 24 June, Rep. Alexandria Ocasio-Cortez (D-NY-14) introduced the House version of the Artificial Intelligence Data Center Moratorium Act — H.R. 9442 — with a Senate companion led by Bernie Sanders. This one is not about federal land at all. It would halt construction or upgrading of AI data centres nationwide until Congress enacts laws meeting a list of safety, economic and environmental conditions. Its definition is specific rather than sweeping: a facility used to develop or operate AI models at scale, or one drawing more than 20 megawatts that is built to deliver 20kW or more to a single rack or to use liquid or immersion cooling. An ordinary enterprise data centre is not covered. The bill would also ban US exports of AI computing infrastructure to countries lacking comparable safety and environmental laws, and mandate quarterly reporting on each centre's water use, energy use, wastewater discharge, financial vehicles and worker wages.

"Congress has a moral obligation to stand with the American people and stop the expansion of these data centers until we have a framework to adequately address the existential harm AI poses to our society," Ocasio-Cortez said. "We must choose humanity over profit."

Grijalva, McGovern and Watson Coleman co-sponsored both bills; Tlaib co-sponsored the moratorium herself.

Why the asymmetry matters

Three efforts, one target. The two that would actually halt the buildout are standalone bills referred to committee, backed by advocacy coalitions, with no realistic path in a Republican-controlled House. The one with force is a narrow procurement provision that most coverage of "Congress versus data centres" does not mention, because it does not read as an AI story at all.

The committee's own handling makes the point. When Rep. John Garamendi (D-Calif.) offered a data-centre amendment at the Armed Services markup — requiring assessment of energy, water, grid, security and community impacts before construction — the committee voted it down, though it did separately direct the defence secretary to study community impacts before on-site construction begins. Rep. Derrick Van Orden (R-Wis.), opposing Garamendi's provision, argued that blocking data centres on bases would push them onto farmland and "stand in the way of us maintaining AI dominance over China." Committee chairman Rep. Mike Rogers (R-Ala.) has framed the stakes the same way: "The nation with the best data infrastructure will possess a decisive advantage in the next warfare. The U.S. cannot afford to lose this position."

Restrictions framed as environmental lost. A restriction framed as China policy passed.

That is how AI infrastructure policy is being made in the United States at the moment: not through the bills written about AI, but through defence authorisation language about printed circuit boards. The moratorium bills state a position. The NDAA provision would change what the Army can sign.

It also means the constraint most likely to bind the Pentagon's AI buildout is China — not electricity prices, not water, not Tlaib's concern about integrating "largely untested hardware and software" into military decision-making. Those arguments are being made loudly and losing. The supply-chain argument is being made quietly and winning, over the Army's objection.

Worth watching: whether the provision survives conference with the Senate, and whether the Army's "federal land penalty" argument gets it stripped before the NDAA is enacted. A provision that passes the House is not law.

We have covered what data centres have actually done to electricity bills, which is the cost argument these bills are reaching for.

Note on sourcing: congress.gov is inaccessible to us, so bill records, dates and the roll-call result here come from the Government Publishing Office's govinfo service. Characterisations of the bills by their sponsors are attributed as such.