On September 19, Germany will honor a speech, delivered 25 years ago, with a permanent plaque on the very spot where President Reagan gave it in front of Berlin’s Brandenburg Gate. It was there that on June 12, 1987, Reagan uttered the most famous words of his presidency and perhaps the entire Cold War: “Mr. Gorbechev, tear down this wall.” He was of course talking about the Berlin Wall, which did indeed come crumbling down two years later, taking with it the entire Soviet Empire.

For Reagan, the speech was 20 years in the making. As early as 1967 when Ronald Reagan was Governor of California, he began asking for the destruction of the wall. In a debate with Senator Robert Kennedy, he said, “it would be very admirable, if the Berlin Wall, which was built in direct contravention to a treaty, should disappear.”

Fast forward to 1986. Negotiations from the Reykjavik Summit had stalled and Gorbachev noted after visiting the Berlin Wall that “At the Brandenburg Gate, one can clearly see how much strength and true heroism the defense of the first socialist state on German soil requires against the attacks of the class enemy.”

Reagan was undeterred. He was anxious to make a statement that would echo throughout the West and reverberate behind prison gates in the East. His goal was to put freedom on the offensive and into the heart of the tottering Soviet empire.

Scheduled to attend the Venice Economic Summit in Italy, the President received an invitation from Helmut Kohl to deliver an address during Berlin’s 750th anniversary. Reagan had found the opening he was seeking. Initially, the old Reichstag, which formerly housed the German Parliament, was to be the location for his remarks but Reagan’s advance team persuaded the skeptical West Berlin officials that the event should be staged in front of the visually impressive and politically sensitive Brandenburg Gate. Reagan knew it was a provocative location that suited his objectives well.

As for preparation of his speech, many of President Reagan’s own advisors preferred a softer message that would avoid ruffling communist feathers. After all, the recent confrontational Reykjavik Summit had brought about a stalemate in arms talks.

“No chest thumping. No Soviet bashing, no inflammatory statements about the Berlin Wall,” is what White House speechwriter Peter Robinson recalls hearing from staff preparing the President’s trip. It was at a dinner with Berlin residents where Robinson conceived the idea of Reagan asking Gorbachev – if he was really serious about this perestroika and glasnost – to tear down the wall.

Once the wording was in, Reagan’s advisers urgently requested he remove the “provocative” language. It would raise false hopes, they said.

A few days before the speech, President Reagan grew restless with the timidity of some of his staff. He reminded his advisers, “I’m the President, right?”

So at last, on a cold spring day at the Brandenburg Gate in Berlin in 1987, he delivered his famous speech, with his words, in his tone, wearing a new blue suit and his lucky cufflinks that Nancy had given to him. He spoke to tens of thousands of attentive West Germans while the imprisoned residents of East Berlin huddled on the other side, straining to hear his message despite the efforts of Communist leaders to squelch his words from the West. Expecting “provocative and slanderous abuse of the DDR,” Stasi Chief Erich Mielke panicked and ordered a general alert with the highest amount of vigilance on the part of the secret police.

“The Soviets will be unhappy,” Reagan recorded in his diary of that day. That was only the beginning.

After the speech, he diligently continued his campaign for freedom. As historian Steven Hayward documented, over “the next year and a half before he left office, repeated the call to tear down the wall another fourteen times: four times in his Saturday radio addresses, 3 times in special radio broadcasts to Europe, 5 times in speeches to U.S. audiences, and twice during interviews with foreign journalists.” While the Soviets squirmed and the East Germans worked on reinforcing the wall, U.S. intelligence began observing increased cable traffic from Moscow to East Germany suggesting that East Germans ease restrictions on passing through the wall.

The Berlin Wall finally fell in November 1989, 29 months after President Reagan ignored the naysayers. Solidarity came to power in Poland, with Czechoslovakia following. Wrote Marian Krzaklewski, chairman of Solidarity, “Ronald Reagan was the main author of the victory of the free world over the evil empire.” In a final gesture, the Warsaw Pact was dissolved and the three Baltic republics that had disappeared with the 1939 deal between Hitler and Stalin – Lithuania, Latvia, Estonia – reclaimed their independence.

They fell to freedom like dominoes – after the President’s words pushed the first one over. One cannot ignore how his powerful conviction ended the Cold War by firing a verbal salvo, an oratorical demand to let freedom prevail.

As he said at the time of his demand, “It wasn’t merely a polite suggestion.”

John Heubusch is the Executive Director of the Ronald Reagan Presidential Foundation and Library and will attend today’s plaque ceremony in Berlin.