On this day in 1987, President Ronald Reagan stepped up to the mic in West Germany and delivered one of history’s most iconic speeches.

Reagan was affectionately known as “The Great Communicator,” a fitting name for a man who spent a lifetime perfecting the art of communication. After starting his career as a sports radio broadcaster in the Midwest, he took his communication abilities to the big screen when he became a Hollywood movie star. He then became the Television face of General Electric, as host of “General Electric Theater.”

In 1964, Reagan shook the political world with his breakthrough speech in support of Republican presidential candidate Barry Goldwater. The speech would come to be known as the “Time for Choosing” speech.

In the address, Reagan said that “freedom is never more than one generation away from extinction. We didn’t pass it to our children in the bloodstream. It must be fought for, protected, and handed on for them to do the same, or one day we will spend our sunset years telling our children and our children’s children what it was once like in the United States where men were free.”

Reagan would go onto deliver many more speeches of similar quality. His 1976 Convention speech laid the foundations for his victory four years later. His first inauguration speech proclaimed that “Government is the problem,” and worked to restore American patriotism. His “Evil Empire” speech challenged the Soviet Union, putting them on notice. His speech commemorating the 40-year anniversary of D-Day honored the sacrifices of a generation. His speech following the Challenger Space Shuttle tragedy consoled a grieving nation.

Then in 1987—with the backdrop of the Brandenburg Gate behind him—Reagan gave arguably his most famous speech of all time.

Built in 1961, the Berlin Wall separated East Germany from West Germany and prevented anyone from crossing from one side to the other. The West Germans lived in a free, capitalistic society, while the East Germans were forced to live under a repressive socialist regime. In time, the Wall became a symbol of the ideological struggle between the United States and the Soviet Union.

The planning for Reagan’s speech began weeks before. There was significant controversy over the initial draft turned in by speechwriter Peter Robinson. In fact, the call to “tear down this wall!” had been taken out multiple times by Reagan’s advisors.

Reagan had a decision to make: should he leave the line in or not?

Most of his top advisors, along with the State Department, wanted him to omit the line in the speech, fearing that it would be too provocative and would upset the Soviet Union, particularly Mikhail Gorbachev, the current Soviet President.

In dramatic Hollywood fashion, Reagan waited until the last moment to make his decision. His Deputy Chief of Staff, Ken Duberstein, rode with Reagan in the limousine to the Brandenburg Gate. He recalled the moment when Reagan made his decision: “We were in the limousine on the way to the Brandenburg Gate and he was reviewing the speech text one last time. He was not using a teleprompter—he was using prepared remarks and paper. When he got to the section of the speech that was disputed by the State Department, he looked at me and said, ‘it’s gonna drive the State Department boys crazy, but I’m gonna leave it in.”

The rest was history.

It is hard to imagine that speech without that famous line. In fact, had it been omitted, the speech probably wouldn’t be remembered at all.

In brilliant fashion, Reagan used the Berlin Wall as a metaphor to paint a vivid picture of the differences between the Democratic West and the Communist East.

He said, “behind me stands a wall that encircles the free sectors of this city, part of a vast system of barriers that divides the entire continent of Europe… In West Germany and here in Berlin, there took place an economic miracle…the leaders understood the practical importance of liberty—that just as truth can flourish only when the journalist is given freedom of speech, so prosperity can come about only when the farmer and businessman enjoy economic freedom.”

Then the famous line came. What he said next would go down in history: “General Secretary Gorbachev, if you seek peace, if you seek prosperity for the Soviet Union and Eastern Europe, if you seek liberalization: Come here to this gate! Mr. Gorbachev, open this gate! Mr. Gorbachev, TEAR DOWN THIS WALL!

The crowd erupted.

Two years later, the Berlin Wall would be torn down and reduced to rubble.

Two years after that, the Soviet Union would be no more.

And all of this was thanks, in large part, to the leadership and courage of Ronald Reagan.