The Erosion of the U.S.-Centric Order and the Emergence of Autonomous Security Blocs

The international system historically anchored to American primacy, consolidated in the aftermath of the Second World War, is now undergoing a structural weakening. This decline is due not only to external challenges but also to self-inflicted setbacks by the United States itself. The core pillars of the U.S.-led order—economic leadership, military dominance, diplomatic authority, and multilateral stewardship—have eroded, diminishing the country’s ability to sustain global influence. Oscillating foreign policies and recurrent isolationist impulses have compromised Washington’s credibility, undermining the trust of its traditional allies. Simultaneously, the emergence of new power centres has rendered collective responses to crises more fragmented and less effective. In this shifting context, a growing number of regional blocs are no longer able—or willing—to rely on the United States for stability and are instead moving to organise their own security and defence frameworks.