When dizzying change sweeps the world, foreign-policy experts often turn to history to find precedents for the headlines. They want to reassure themselves that there is nothing entirely new under the sun and perhaps even to find clues to the future. The current upheavals in Eastern Europe have inspired comparisons to another revolutionary year in European history. In recent weeks former presidential National Security Adviser Zbigniew Brzezinski, Columbia University historian Fritz Stern, and editorial writers in the New York Times and Boston Globe have drawn parallels between 1989 and 1848.
The Springtime of Nations, as the 1848 events were known, was...