Personality and ideology were the main factors which led to the Sino-Soviet split, according to Sergey Radchenko, a fellow in the London School of Economics' International History Department and author of Two Suns in the Heavens: The Sino-Soviet Struggle for Supremacy, 1962-1967. While some scholars explain the split in purely ideological terms, Radchenko argued that "unequal treatment" of the Chinese on the part of the Soviet leadership was the main irritant in the relationship and fueled the ideological clash.

According to Radchenko, Soviet leader Nikita Khrushchev believed, the unequal relationship between the USSR and the PRC was justified by the Soviet Union's status as the world's first communist nation, its role in the defeat of Germany during World War II, and its technological superiority, as evidenced by the launch of Sputnik. Ethnic prejudice also played a role. The writings of 19th Century Russian explorer Nikolai Przhevalsky—who described the Chinese as untrustworthy, cowardly and lazy—influenced Khrushchev and the Soviet politburo and reinforced seeing the relationship between the two nations in hierarchical terms.

Chinese leader Mao Zedong, by contrast, felt that his ascent to power through his leadership during the Chinese Civil War superseded that of Khrushchev, whom he viewed as one of Stalin's lackeys. With Stalin deposed by Khrushchev's de-Stalinization campaign, Mao thought that he—not Khrushchev—should be the leader of the global communist movement.

After Khrushchev's removal from office in 1964, the Soviet leadership made an attempt to ‘mend fences' with the Chinese, yet many factors Radchenko posited, including the relative inexperience of the new Soviet leadership and a fear of appearing weak at home, stood in the way of a compromise with the Chinese

By 1965-1967, the Soviets' efforts to isolate China were being met with success. China was in the midst of its Cultural Revolution and suffered important failures in both domestic and foreign policy, Radchenko averred.

Stepping outside the Sino-Soviet paradigm, Radchenko pointed out that Stalin, like Mao too had been sensitive about the perceived inequality in his relationship with the U.S. yet it seems that the Soviets never drew parallels between this experience and their relationship with the PRC.

James Hershberg expanded upon this notion of a ‘trickle down theory of international relations' by pointing out that the Chinese, too, could have drawn similar lessons and applied them to their relationships with North Korea and North Vietnam, but did not.

Largely agreeing with Sergey Radchenko's analysis of the Sino-Soviet split, Mark Kramer pointed out that differences in ideology between the two nations also played an important role, while underlining the fact that ideology alone could not have been the sole cause of the rift.