I am sitting in my glass-walled office in Berlin, overlooking Friedrichstrasse. My office is in one of the many building that line the street, all built with the clean, sharp aesthetic that defines modern German architecture, each building's form following the building's function.

In the mornings the street is crowded with cars, tourists, trucks, buses and cyclists like me, weaving in and out of all of them. At night, when I ride home, the crowds are smaller and the ride more leisurely. There are few street lights; the pink, yellow and blue glow coming from the neon signs of high-end shops make them almost unnecessary. It's a pleasant ride, and for my first few days here in Berlin I marvelled at its uniqueness. Berlin is not like any other city I've seen. But like all things, after a while, the ride became normal and routine, just a way for me to get from here to there, from work to home. Friedrichstrasse could be any other street in any other city.

This isn't any other street. This was once the heart of East Berlin. For more than four decades, Friedrichstrasse and the area around it were a wasteland, a lifeless victim of the Cold War.

Two blocks south of my office is historic Checkpoint Charlie, the militarized access point formerly dividing East and West Berlin.

In 1961, Soviet tanks sat just beneath my window, pointing their cannons at American tanks, which were positioned on the West German side of the street. A few blocks north is Brandenburg Gate, which for centuries served as a unifying symbol of Germany. During the Cold War, it served as a reminder of the divisions within Germany, between East and West, between communism and democracy, between the United States and the Soviet Union. There were two sides. Choose one. Unless, of course you were behind the Iron Curtain, where the choice was made for you.

Twenty years ago tomorrow, East Berliners made their own choice. Protests against Soviet occupation had been occurring for months around Germany. But what happened in Berlin appeared destined.

As if scripted by history, hundreds of thousands of East Berliners, marching up streets like Friedrichstrasee to the Berlin Wall in front of the Brandenburg Gate, demanding to be let through to the West. The night was spontaneous, unexpected, and for those who lived through it a bit terrifying -- imagine if the world you had lived in for four decades suddenly was no more. Imagine the fear you would feel as you crossed through to West Berlin, knowing that the East Germans guards in the gun tower over your shoulder had standing orders to shoot anyone who attempted to cross.

These were acts of defiance and acts of courage. No shots were heard that night, or the next night, or the nights after that. If there were shots, they would have been drowned out by the sound of metal striking concrete, or of people crying after being reunited with family and friends, of the Wall coming down and an empire collapsing.

There I was, 11 years old, watching it all on the evening news in Pittsburgh, feeling as if the United States -- the good guys -- won. Who were the bad guys? The Russians. Who were the Russians? The bad guys. That was the extent of my understanding of the politics of that night; I would think this understanding was probably shared by the majority of Americans.

But how much do politics matter to a country where students once hid under a desk to prepare for a nuclear attack, as if a desk would make a difference? Those days were done. There would be no longer be mutually assured destruction. The Cold War was over, or at the least coming to an end.

The good guys won. What would Berlin been like if the good guys lost? Look out your window, across the street to a neighbor's house. Now imagine a 10 foot concrete wall in front of your house, and a matching one in front of your neighbor's home. This wall stretches for miles, across the city. In between the walls in an open space; it's easier to shoot a target when they don't have cover. Think about your best friend, your mother, your grandmother. Imagine wanting to see that person on a birthday or holiday. But they live on the other side of the wall, and you risk imprisonment, even death, if you want to visit them. Maybe you see them once a year, maybe once every five years, maybe never.

That was life in East Berlin when the bad guys were in charge. But that was over on Nov. 9, 1989. The good guys won.

What happens when the good guys win? They have to sit down with the bad guys to make it formal. So there they were, President George H.W. Bush, Soviet General Secretary Mikhail Gorbachev, meeting in Malta a few weeks after the Wall fell. West German Chancellor Helmut Kohl followed progress from Germany. No agreements were signed at Malta, but many consider it the end of the Cold War. For better or worse, each of these men would be remembered for the part they played in bringing it to peaceful a close.

And here they are, 20 years later, Bush, Gorbachev and Kohl, in front of nearly 2,000 dignitaries in a German theater on Friedrichstrasse. All three are still recognizable, but the years have taken their toll. Gorbachev has gained weight and Bush now uses a cane to walk. Kohl has fared the worst of the three, confined to a wheelchair after a suffering a stroke. And behind them is German Chancellor Angela Merkel, the first chancellor from the former East, who hides her effectiveness as a statesman behind a reserved manner fitting for the daughter of a Lutheran minister.

Everyone takes their seats, and after a series of long speeches by German politicians, Bush, Gorbachev and Kohl sit together on the dais and deliver their remarks. Bush has a speech prepared, but goes off script when he leans over to talk to Gorbachev, who he calls "Mikhail." Gorbachev speaks for a while, without notes. He apologizes to Kohl for not seeing the end of communism sooner. Kohl doesn't say much, the stroke having severely hindered his ability to communicate.

It's a strange feeling, seeing this in person. It was an honor to be there, but I'm not moved by the event itself. What does move me are the faces of my German friends-- they are the ones transfixed by seeing these men celebrating the most important event in modern German history.

Each of my friends has different recollections of November 1989. Some have exciting stories; others were angry because in the weeks after the Wall fell, there was a chocolate shortage due to surging demand from the East. Even those who say that November passed without much change now appreciate the importance of the events in Berlin and around Germany. They appreciate the role these three leaders had in shaping them.

The body language between Bush and Gorbachev is not that of statesmen, but longtime friends. They exchange a few quips away from the microphones. Time has scrubbed away bad memories or feelings they had for one another. They're probably thankful that they governed at a time when the enemy had a face and was easy to define.

Gorbachev, once leader of the enemy, now appears to be the opposite. He and Bush appear to be friends.

There was Sven Merkel (no relation to the current chancellor), an 18-year-old East German soldier patrolling the border between communist Saxony and democratic Bavaria in November 1989. At the time, most Americans would consider him a bad guy. It was his job to fight if the Cold War turned hot. And in the weeks before Nov. 9, many in the East feared the war was getting warmer.

Merkel didn't join the military by choice. In East Germany, men were required to serve for at least a year. His year happened to be 1989. As protests against Communist rule multiplied across East Germany, he began to sense uneasiness in his superior officers.

"There were some very smart officers," Merkel said. "But there were some very dumb ones. None of us knew what they would do [if the Wall fell], and they had access to some very strong weapons."

"There was always the question of what we would do if we were ordered to the border if there was an uprising," he added. "If you get on a truck with machine guns to confront other Germans it's already too late. There are thousands of people angry at you. What do you do if you have to defend yourself?"

Merkel and his fellow soldiers had a choice. If ordered to the front, they could go, setting aside an uneasy feeling that something horrible would happen. Or they could disobey orders and face a lifetime in an East German prison.

"Our decision was to be arrested if the order to go came that night," Merkel said.

It didn't. By December, Merkel said it was clear East Germany had seen its end.

Then there was Merkel in 1994, studying and teaching German at Ohio State University. One fall evening he and his colleagues went on a hayride, followed by a barbeque and a bonfire. He got to talking to one of the guests, an American who had served in the Army along the West German border in 1989. The officer was stationed directly across the border from Merkel. He told Merkel that he was just as uneasy on Nov. 9, 1989, as his counterparts in the east.

"We talked for quite a while and were thankful that we were sitting there by a fire and didn't meet while fighting," Merkel said. "It was funny to come all the way to Columbus and see someone who was there on the same night, at the same time, on the other side."

And here we are, Sven Merkel and I, talking over a beer at a bar in Berlin.

Sven, now 38, is the resident director for Brown University in Germany. It's his job to see that Brown students studying here have a positive experience, which makes him a chaperone, psychologist, academic adviser and cultural attache.

Sven and I talk about his experience as a solider, about how so much has changed in the last 20 years in Germany and Europe, about how the world has changed so much since the Soviet Union collapsed. The end of communism has allowed people like Sven to travel freely around the continent, so much so that he feels more and more like a citizen of Europe.

I pass him a copy of Kurt Vonnegut's "Slaughterhouse Five," about the Allied firebombing of Dresden during World War II. He hasn't read it. I tell him it shows that the good guys can do some pretty horrible things. Good and evil are never as simple as we'd like them to be.

After we part ways, I ride my bike home through the empty streets of Berlin. I think of all the things that had to happen to get me to Berlin, to the chair at the table where I had a beer with a former East German soldier who was a loose trigger-finger away from World War III. About the tanks at Checkpoint Charlie, about the courage of the people who climbed the Wall on Nov. 9, about watching in amazement from Pittsburgh. I think about Bush, Gorbachev and Kohl and their role in ensuring a peaceful revolution remained that way.

Then I think of all the labels people have applied to these things over the years, these good men or evil men, about how these labels are simplistic and usually only add to misunderstandings.

As a solider, Sven was never an enemy, he was never part of an evil empire, and he never wished the United States or its citizens harm. He, like those who first passed from East Berlin, under the Brandenburg Gate, into West Berlin, showed tremendous resolve in the face of uncertainty, even death. People like Sven are responsible for changing history in 1989.

So now, sitting in my office along Friedrichstrasse 20 years after the Berlin Wall fell, the only label I would apply to Sven is friend.

Cartoonist Rob Rogers does "Rob's Rough," an early look at his work and his creative process, exclusively at PG+, a members-only web site of the Pittsburgh Post-Gazette. Our introduction to PG+ gives you all the details.