Sen. Elizabeth Warren is pressing the U.S. Commerce Department for answers about how it is handling national security concerns tied to Bitmain, the Chinese manufacturer that supplies a large share of the world’s Bitcoin mining equipment. Warren sent a letter — reported by Bloomberg — to Commerce Secretary Howard Lutnick on Thursday requesting documents and communications related to Bitmain and any steps the department has taken to address “potential national security concerns.” Her inquiry also asks whether political influence has played a role in how the matter is being handled. The push comes amid months of federal scrutiny. A Department of Homeland Security probe, dubbed Operation Red Sunset, has examined whether Bitmain’s mining rigs could be remotely accessed or otherwise used for espionage or sabotage that might threaten U.S. systems. A separate federal review in May 2024 reportedly raised “national security concerns” after Bitmain machines were found operating near a U.S. military base. Bloomberg notes these national security investigations can remain open for years without public enforcement action. The concerns are amplified by the highly concentrated ASIC mining-hardware market. Cambridge University’s Digital Mining Industry Report found the top three manufacturers control more than 99% of the market, with the single largest vendor holding about 82% — underscoring how much U.S. miners rely on a small number of foreign suppliers. Regulatory and trade measures have already had real-world effects. In February 2025, customs scrutiny delayed deliveries of Bitmain equipment to U.S. miners. Taiwan Semiconductor Manufacturing Co. (TSMC) halted shipments to Sophgo — a chip designer linked to Bitmain — after a chip connected to Huawei was identified, and Sophgo was later placed on a U.S. trade blacklist. Those actions broadened scrutiny beyond mining hardware to Bitmain’s wider business relationships and how Chinese crypto-hardware suppliers intersect with U.S. trade and security policy. The political dimension deepened after Bloomberg reported that American Bitcoin, a mining firm backed by Eric Trump and Donald Trump Jr., agreed last year to buy 16,000 Bitmain rigs for $314 million, according to securities filings. Warren’s letter requests any communications between Bitmain, Commerce officials, and Trump family interests. At the same time Bitmain has been expanding its U.S. footprint: in July 2025 it announced plans for a first U.S.-based manufacturing site, with initial output expected in early 2026 and a larger ramp later that year. That expansion now sits alongside an unresolved federal review and increasing political scrutiny in Washington — leaving U.S. miners, policymakers, and industry watchers watching closely for how the situation unfolds. Read more AI-generated news on: undefined/news