On a summer morning in Rio de Janeiro in mid-2025, the leaders of the BRICS nations convened for the bloc’s 17th summit. The scene was one of carefully choreographed cooperation, yet the air was thick with an unmistakable tension. While the presidents of Brazil, India, and South Africa publicly discussed diversifying trade and promoting transactions in national currencies—a veiled challenge to the primacy of the U.S. dollar—their aides were in frantic communication with Washington. The reason for this tension is that an aggressive new round of American tariffs threatened the very countries that are seeking greater economic autonomy. This moment encapsulates the central dilemma defining the 21st-century global order: a simultaneous pursuit of engagement with competing economic and security systems, led by the United States and China.