DJ Rosenthal is a national security lawyer whose career spans the White House, the U.S. Intelligence Community, the Department of Justice, and some of the most consequential cross-border transactions of the past decade. As Senior Advisor at Bellementis and Founder of 77 Meridian Law & Policy, he advises defense contractors, technology companies, and investors on the legal and strategic challenges that define operating in today's geopolitical environment—from international trade matters such as CFIUS reviews, export controls, and sanctions compliance, to legal and policy matters regarding emerging technologies, intelligence, and national defense and public safety.

DJ brings a rare combination of insider experience and practical legal judgment to client work. As Director for Counterterrorism at the National Security Council, he advised the President's senior staff on emergent threats, helped manage the U.S. Government's counterterrorism activities, and worked at the nexus of law, intelligence, and policy. Earlier, as Senior Counsel to the Assistant Attorney General for National Security at DOJ, he advised on foreign investment matters before CFIUS, government surveillance reform, and sensitive operational matters. And as Senior Associate General Counsel at the Office of the Director of National Intelligence, DJ provided legal guidance on intelligence operations, national intelligence policy, and congressional and public engagement.

After government service, DJ co-founded and led Kroll's National Security and CFIUS Advisory practice, advising foreign and domestic clients on inbound investment reviews and national security compliance. He then served for nearly seven years as Executive Director at ProShares, where he led regulatory strategy and high-stakes government engagement for one of the country's largest ETF providers. That combination of government credibility and private-sector fluency is what clients value most—DJ understands how regulators think, how agencies act under pressure, and how to position organizations for the best possible outcomes.

DJ is the Founder and Principal of 77 Meridian Law & Policy, LLC, a boutique national security consulting firm offering specialized legal counsel, strategic risk management, and technology security. DJ also serves on the Advisory Council of the Spades Institute and acts as its legal counsel. He has taught National Security Dilemmas at the University of Maryland Honors College since 2013, where he developed the seminar's curriculum from the ground up. He is a widely published voice on national security and international trade, with work appearing in The New York Times, The Atlantic, CNN, Foreign Policy, Politico, The Hill, Lawfare, and Just Security, among others. He also co-authored an amicus brief filed before the D.C. Circuit in the landmark U.S. Steel v. CFIUS case and has been a signatory to numerous amicus briefs filed with the United States Supreme Court relating to national security, technology, and public safety.

DJ's areas of expertise span international trade regulation and CFIUS, export controls and sanctions (EAR/ITAR/OFAC), defense and intelligence sector advising, counterterrorism law and policy, cross-border transactions and geopolitical risk, and national security law and compliance.