South Asia In The Post Cold War Era

To determine the leader of the Soviet Union who proposed the Asian Collective Security System, we analyze the given options:

1. Nikita Khrushchev: Led the Soviet Union from 1953 to 1964, but was not known for initiating the Asian Collective Security System.
2. Leonid Brezhnev: Holds leadership from 1964 to 1982, and during his tenure, he indeed proposed the Asian Collective Security System. His policy focused on enhancing collective defense and economic cooperation in Asia as part of his broader foreign policy initiatives.
3. Boris Yeltsin: Known more as a post-Soviet leader, serving as President of Russia from 1991 to 1999.
4. Vladimir Lenin: The leader of the Bolshevik Revolution and head of the Soviet state until 1924, far earlier than the proposed system.

Based on the historical context and tenure, the correct leader is Leonid Brezhnev.