Senator Elizabeth Warren sent a letter to Commerce Secretary Howard Lutnick on March 20 demanding documents related to a federal investigation into Bitmain Technologies, the Beijing-headquartered company that manufactures the majority of the world's Bitcoin mining hardware. The probe, codenamed Operation Red Sunset, examined whether 16,000 Bitmain machines purchased by a Trump family-backed mining venture could be remotely accessed or used to disrupt the US power grid.
Bloomberg reported the letter's existence on March 27. The inquiry lands at an awkward intersection: Lutnick, a Trump appointee, is being asked to produce national security materials about a company whose equipment is used by a venture his boss's sons co-founded.
16,000 Machines, $314 Million, and a Military Base
American Bitcoin, a mining venture backed by Eric Trump and Donald Trump Jr., acquired approximately 16,000 Bitmain mining rigs through an agreement inherited from HUT 8 subsidiary Zephyr. SEC filings put the deal at up to $314 million for around 17,280 Bitmain U3S21EXPH miners.
The security concerns surfaced in May 2024 when one of the mining facilities operating Bitmain hardware was flagged for its proximity to a US military base. The Department of Homeland Security launched Operation Red Sunset under the Biden administration to determine whether the machines could be weaponized, either for espionage or for disrupting the electrical grid through coordinated remote shutdown or overload.
The Senate Select Committee on Intelligence published a report in July that assessed "there is a possibility of tampering with equipment from China and multiple vulnerabilities exist." The committee described the vulnerabilities as "disturbing" and warned that the machines could potentially be "manipulated from China."
Why Warren Wrote to Lutnick
Warren's letter requested "materials on the status of any Bitmain-related investigation and potential response measures." The choice of recipient is pointed. Lutnick, who took over the Commerce Department under Trump, previously ran Cantor Fitzgerald and has his own extensive ties to the crypto industry, including Tether's custodial relationship with Cantor.
Warren has spent the past year escalating scrutiny of Trump family crypto ventures. In February, she demanded hearings after the Wall Street Journal reported that a UAE intelligence chief secretly acquired a 49% stake in World Liberty Financial, the Trump-linked DeFi project, for $500 million. That deal, signed by Eric Trump, reportedly sent $187 million to Trump family entities.
The Bitmain letter adds a national security dimension that goes beyond conflict-of-interest questions. If Chinese-manufactured mining hardware can be remotely controlled, the risk extends to any US mining operation running Bitmain equipment, not just the Trump-affiliated one.
Bitmain Controls Most of the Market
Bitmain's dominance in the ASIC mining hardware market is the core issue. The company manufactures an estimated 80% or more of the world's Bitcoin mining rigs. Its Antminer series is the industry standard, used by publicly traded miners, private operations, and sovereign wealth fund-backed ventures alike.
That market position means any confirmed vulnerability would have implications far beyond American Bitcoin. Major US-listed miners including Marathon Digital, Riot Platforms, and CleanSpark all run significant fleets of Bitmain hardware. If Operation Red Sunset found evidence of remote access capability, the entire US mining sector would face a supply chain reckoning.
Bitmain denied all allegations. The company stated that reports are "largely inconsistent with the facts and false" and that claims of remote control capability are "unequivocally false." Bitmain said it "strictly complies with US and applicable laws" and had no knowledge of Operation Red Sunset.
What Stays Classified
The investigation's findings remain undisclosed. National security probes can stay nonpublic for years, and there is no guarantee that Warren's request will produce declassified materials. The Commerce Department has not publicly responded to the letter.
The political dynamics complicate any resolution. Warren, a Democrat, is asking a Trump-appointed Commerce Secretary to produce potentially damaging information about a venture co-founded by the president's sons. Lutnick has no legal obligation to share classified investigation materials with a senator outside the relevant oversight committees.
Bitcoin is trading at $66,264 as of March 28, 2026, down 3.4% over the past 24 hours and 6.3% over the past week. The Fear and Greed Index sits at 23, in "Fear" territory. Mining stocks have been under pressure alongside the broader crypto market, with hash price near historic lows.
Overview
Elizabeth Warren is demanding documents from Commerce Secretary Howard Lutnick about Operation Red Sunset, a DHS investigation into whether 16,000 Bitmain mining machines near a US military base could be remotely manipulated from China. The machines belong to American Bitcoin, a venture backed by Eric Trump and Donald Trump Jr. through HUT 8, which paid up to $314 million for the rigs. The Senate Intelligence Committee found "several disturbing vulnerabilities." Bitmain denies all allegations. The investigation's classified findings remain unreleased, and the political dynamics between a Democratic senator and a Trump-appointed Cabinet member make disclosure unlikely without congressional action.
