President John F. Kennedy stands on an observation platform near Checkpoint Charlie to look over the Berlin Wall toward East Berlin on June 26, 1963. (AP)

In his famous 1963 speech, President John F. Kennedy proclaimed to the world, “Ich bin ein Berliner,” showing solidarity with a divided city at the center of the Cold War. But new revelations suggest that he was far more circumspect about those fleeing East Berlin's brutal communist regime.

The new book “The Tunnels: Escapes Under the Berlin Wall and the Historic Films the JFK White House Tried to Kill” shows the trade-off behind the scenes at one of the most pivotal moments in the standoff between the United States and the Soviet Union.

According to the book's author, Greg Mitchell, the Kennedy administration, for fear of “provoking” the Soviets, tried to suppress the screening of two documentaries about the escape tunnels underneath the Berlin Wall.

In one case, the government interference was successful, causing CBS to ax a report by its correspondent Daniel Schorr. NBC, however, refused to bow to the State Department's pressure and proceeded to screen a similar documentary — although with several weeks' delay.

When construction of the wall began in August 1961, many Berliners were surprised. Families and friends were separated from one day to the next. Many, especially among those who found themselves stuck in the east, desperately tried to cross to the other side in every imaginable way. But the East German authorities cracked down hard on those trying to flee. The only option left seemed to be going underground. Adventurous, mostly young Germans dug dozens of tunnels in subsequent years, enabling hundreds of their fellow citizens to escape. But dozens were also arrested; some were even shot and killed in the attempt.

Mitchell sifted through thousands of pages of previously classified State Department, CIA and East German secret police files, cables and other documents about the tunnels. The result is a fascinating and complex picture of the interplay between politics and media in the Cold War era.

On Aug. 7, 1962, the day of a planned mass tunnel escape that Schorr hoped to cover, Secretary of State Dean Rusk summoned CBS executive Blair Clark, a longtime Kennedy friend, to his office and asked him to scrub the project. Clark succumbed to the pressure and called Schorr off. Schorr remained bitter about it until the end of his life. The escape itself failed because of a snitch among the ranks of the tunnel diggers, resulting in several arrests.

The U.S. government at the time was supporting the East Germans' quest for freedom only publicly, Mitchell said in an interview with The Washington Post. “Privately they thought, there's not much we can do ... if we don't want to start World War Three over it.”

Instead of being concerned with a few refugees, the Kennedy administration was “anxious to protect West Berlin,” Mitchell said. “The Soviets would have accused the White House of being behind it.... To have TV involved and to film the escape would make it seem to them as if surely this has government approval.”

President John F. Kennedy delivers a speech in front of the city hall in West Berlin on June 26, 1963. (AP)

What the State Department didn't know at the time and CBS reporter Schorr could only suspect was that CBS's competitor, NBC, already had its own tunnel documentary in the pipeline. Journalist Piers Anderton and producer Reuven Frank had learned about a group of West German students, including East German refugee Hasso Herschel, who were working on a tunnel leading from factory grounds in the west to an East Berlin basement. On Sept. 14 and 15, 1962, 29 people managed to escape in this way, including Herschel's sister and her family, making it one of the most successful tunnel escape operations in German history.

The 90-minute NBC documentary was originally set to be screened on Oct. 31, but the premiere was delayed until Dec. 10, mainly because of pressure from the Kennedy administration. When it finally aired, however, it was widely acclaimed by viewers and critics and wound up winning three Emmy awards.

But there's another twist to the story: NBC not only documented the course of history, it might even have actively influenced it by paying the equivalent of $150,000 to the Berlin tunnel diggers. The money helped them cover their costs and probably even fund future escapes. “Even the tunnel diggers disagree on this,” explained Mitchell, who interviewed several contemporary witnesses with the help of his German-speaking son-in-law. “Some of them said we would have still finished this tunnel without the NBC money.... But most of them said, we needed it.”

Andreas Etges, a historian at the Ludwig Maximilian University of Munich, said it wasn't unusual for a Kennedy administration focused on Cold War politics to try to persuade media outlets to drop or delay their coverage.

“The most important thing for the Americans was that there wasn't another world war,” Etges said. "They were ready to pay the price for that ... even if it meant sacrificing the freedom of the East Berliners.”

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