Communism would have collapsed even without Ronald Reagan but he will be remembered because he put into words what very few dared to say - that something was rotten in the system.
By Paul Reynolds
BBC News Online world affairs correspondent
Making history: Ronald Reagan in Berlin in 1987
"Mr Gorbachev, tear down this wall," he cried in Berlin on 12 June 1987.
It sounded to some at the time like just another Hollywood line.
But it came to pass just over two years later, on 9 November 1989, when the wall was opened and the people of Berlin began to dismantle it.
Mr Gorbachev had previously made clear to the East German leadership that their days were over.
Winning the race
His opponents saw Ronald Reagan's simple and direct language as a weakness and a reflection of an unsophisticated mind. They scoffed at him as the actor who was playing the politician.
But his simplicity turned out to be his strength.
He looked communism in the eye and it blinked.
For this he will be remembered.
He was not one of the greats like Lincoln or Roosevelt. They were presidents on whom the fate of the nation and the world depended. The Reagan presidency mostly made its mark by being inspirational.The battles of his day were battles of ideas and his ideas prevailed.
One problem was that he saw communism everywhere.
Shortly after he came to power, he and his Secretary of State Al Haig decided that the front line ran through Central America, in particular the small country of El Salvador then in the middle of a revolution. They really believed that a thread ran from El Salvador to Nicaragua to Cuba to Moscow. This obsession led to the "contra scandal" which did Ronald Reagan great harm later on.
Central America was really a sideshow, and the Berlin Wall would have fallen anyway, but at the time, President Reagan gave the impression that the fate of the western world depended on what happened among the mountains of those until-then forgotten lands.
More relevant to the downfall of the Soviet Union was his willingness to spend huge sums on armaments and dare the Soviet Union to try to match him. It could not. But in trying to, it lost the race.
With Ronald Reagan what you saw was pretty well what you got. That was one of his strengths. He could make himself appear to be above politics, even though he was a determined and single-minded politician.
Cold War Warriors: Ronald Reagan and Mikhail Gorbachev
I interviewed him in 1979, just after he began running for the presidency against Jimmy Carter. I met him on his campaign plane somewhere over Florida.
He behaved to this obscure foreign radio reporter exactly as he did to the big network anchors.
His ideas and beliefs came tumbling out as fast as the snappy stories which filled his speeches.
He recalled for me his own radio days when he commentated on baseball games, which he could not see, off a ticker tape.
Once the tape broke and all he could do was to make up a number of plays, in which the game carries on without anyone being out, until the line was restored.
It taxed his imagination, he remarked with a smile. Reagan always had a smile.
The late seventies was a bleak time in America.
People thought the country was sliding downhill and that the Japanese were going to take over American and world industry. It was pre-Bill Gates.
There was even a country song with the words: "God Bless America again. You see all the trouble that she's in."
Playing ball: Reagan's informal manner won him many friends
And yet here came this confident ex-governor of California, talking about how wonderful America was.
Jimmy Carter, agonising over the hostages being held in Iran, really stood no chance.
The biggest applause Reagan got at his rallies came from the following simple three lines:
"A recession is when your neighbour loses his job. A depression is when you lose your job. And recovery will come when Jimmy Carter loses his."
He would tell it in speech after speech, sometimes half a dozen times in a day. It never failed.
History will probably record Ronald Reagan as a fortunate president, lucky to be on watch when the Soviet Union began to crumble.
It will argue over how far he and his soulmate Margaret Thatcher contributed to that collapse.
But it will not argue over their supreme confidence that they were right.