The Zhenbao Island conflict in 1969 was a critical event that exacerbated the Sino-Soviet split. This brief but intense military clash over a disputed border island brought the two countries to the brink of a larger-scale war. The conflict highlighted the severity of the territorial disputes between China and the Soviet Union and marked a low point in their bilateral relations. It also reflected the broader ideological and strategic disagreements that had been simmering for years. The conflict led to increased militarisation along the Sino-Soviet border and intensified mutual distrust, making any form of reconciliation even more challenging.

The Sino-Soviet split had significant long-term effects on the foreign policies of both China and the Soviet Union. For China, the split led to a gradual opening towards the West, most notably the United States, as part of its strategy to counterbalance the Soviet threat. This shift culminated in the historic visit of US President Richard Nixon to China in 1972. For the Soviet Union, the split necessitated a reassessment of its foreign policy, particularly in Asia. The USSR sought to strengthen ties with other Asian nations and became more involved in regional conflicts, such as the Vietnam War, to maintain its influence in the face of Chinese opposition. The split also influenced the internal policies of both nations, leading to a more nationalistic and less ideologically driven approach to foreign relations.

The impact of the Sino-Soviet split on other communist nations, especially those in Eastern Europe, was profound. It created a dilemma for these nations, as they were forced to navigate the complex dynamics of aligning with either the Soviet Union or China. Some countries, like Albania, openly sided with China, criticising the Soviet Union for what they perceived as a deviation from Marxist-Leninist principles. The split also emboldened some Eastern European leaders to pursue more independent policies, leading to a loosening of Soviet control over the Eastern Bloc. Furthermore, the split provided a degree of leverage to Eastern European nations, as they could play off the two major communist powers against each other to gain concessions.

Nuclear weapons played a significant role in the Sino-Soviet split, particularly in the escalation of tensions and the shifting balance of power. China's successful detonation of a nuclear bomb in 1964 was a pivotal moment. It not only enhanced China's status as a major world power but also challenged the Soviet Union's dominance in the communist world. The Soviet Union viewed China's nuclear capability with apprehension, fearing it would embolden Mao's independent foreign policy and strategic ambitions. This development further exacerbated the existing ideological and geopolitical rifts, as both nations now possessed a significant deterrent capability, adding a new layer of complexity to their relationship.

The Sino-Soviet split significantly altered the global perception of communism by revealing deep fractures within the communist bloc. Prior to the split, communism was often viewed as a monolithic entity led by the Soviet Union. However, the ideological and strategic disagreements between China and the Soviet Union showcased the diversity and complexity within communist ideology. This fragmentation weakened the image of a unified communist front, leading to a more nuanced understanding of communism globally. Additionally, the split demonstrated that national interests could supersede ideological solidarity, as both China and the Soviet Union pursued policies that prioritised their respective national agendas over communist unity.