For centuries Europe has fought wars over borders. During the 19th century and the first half of the 20th century, Europe’s borders shifted wildly, as empires fragmented, new nations arose and wars were waged. After 1945 and the beginning of the Cold War, a new principle emerged on the Continent. The borders that existed at the end of World War II were deemed sacrosanct, not to be changed. The confrontation of the United States and the Soviet Union in Europe was enormously dangerous. It was understood that border disputes had been one of the origins of the two world wars and that even raising the legitimacy of post-war borders risked igniting passions that led to violence.
Europeans generally accepted that living with unreasonable or unjust borders was far better than trying to get them right. So, during the Cold War, border issues were rarely raised, and when they were, they were usually quickly swept under the rug. The U.S. and Soviet Union were calling the shots, and neither wanted a world war over Europe’s borders, nor did they trust the common sense of European politicians, particularly after the wars of the first half of the 20th century.