On 24 June 1948 the Soviet Union abruptly closed all land and water access to the Western Sectors of Berlin. Over 2 million civilians, dependent on the surrounding territory and the West for food, fuel, and other basic goods, were suddenly cut off from all necessities of life.
The Western Allies had the option of either withdrawing their garrisons and allowing the Soviet Union to take control of the entire city, or of trying to supply the city by air. Never before in history had 2 million people been supplied exclusively by air. None of the senior military commanders believed it could be done.
But the political leadership in London and Washington insisted that it had to be done. A withdrawal from Berlin would discredit the West a a critical moment in history, when the Soviet Union was expanding aggressively across Europe. Worse, it would endanger the political stability and economic recovery of all of Europe.
So one of the largest and most ambitious humanitarian efforts in history was set in motion. It began without the West really knowing what the Berliners needed in order to survive -- much less how much those supplies weighed. It was launched despite a lack of airlift expertise in theater or a unified command structure, an almost complete absence of aircraft and aircrew resources in Germany and serious inadequacies in airfields and air traffic control. But once it began, the Berlin Airlift became an inspirational feat of organization and collaboration and was more of a success than even its originators and advocates had ever imagined possible.