1. The Soviet Blockade was caused because the Soviet's were trying to block the Western supply lines and canals, which would've ended up in the Soviet's taking over the weakened Western points.
2. The event, or events that caused the Soviet's to stop the blockade was: the Cold War and the Berlin Airlift.
3. The event that started the Korean War was when North Korea took over Seoul and most of South Korea, except Pusan.
4. By sending UN troops [primarily the United States] to Pusan, to hopefully take back Seoul.
5. The biggest effect of the Korean War was the new political systems, and the DMZ, or Demilitarized Zone.
[HOPEFULLY THIS IS HELPFUL!]