President Joe Biden announced on January 3 that he is blocking the nearly $15 billion acquisition of U.S. Steel by Japan’s Nippon Steel, citing national security concerns and the importance of maintaining a strong domestic steel industry. This decision, which may strain relations with Tokyo, comes amidst ongoing debates about foreign control over key American industries. The United Steelworkers union expressed support for Biden’s decision, although the stock price of U.S. Steel declined significantly following the announcement.