ChainCatcher news, during a hearing held by the Senate Banking, Housing, and Urban Affairs Committee on Thursday, U.S. Senator Elizabeth Warren questioned Assistant Secretary for Investment Security Paul Rosen from the Treasury Department about the threats posed by foreign-owned cryptocurrency mining operations in the United States.Senator Elizabeth Warren claimed that the U.S. cryptocurrency mining industry poses a threat to national security, stating that "cryptocurrency mining operations run by foreign adversaries" could be used to "monitor U.S. military operations."Warren added that "foreign-owned crypto mines also threaten the power grid, and their connections to the U.S. grid could make the U.S. vulnerable to targeted blackouts and cyberattacks."