After World War II, the Allies partitioned Germany into a Soviet-occupied zone, an American-occupied zone, a British-occupied zone, and a French-occupied zone. Berlin, the German capital city, was located deep in the Soviet zone, but it was also divided into four sections. In June 1948, the Russians–who wanted Berlin all for themselves–closed all highways, railroads, and canals from western-occupied Germany into western-occupied Berlin. This, they believed, would make it impossible for the...