The comparative analysis of different regions plays a pivotal role in comprehending the emerging era of intense great power competition. This article introduces the framework of Maritime Regional Security Order (MRSO), shedding light on intricate interaction patterns among local and extra-regional powers within specific geographical areas, where the nature of interactions ranges from conflict-driven to cooperative regional settings. Within this framework, the South Atlantic and the Indo-Pacific regions are examined as case studies of MRSO, both influenced by shared global dynamics that are facing heightened pressures due to escalating tensions between the United States and the People’s Republic of China. The findings underscore that divergent regional forces are likely to contribute to a higher level of stability in the South Atlantic when compared to the Indo-Pacific region.