To quote The Beatles, "it was 20 years ago today."
Earlier in 1989, East Germans had become more free to emigrate to the West, and to hold public anti-government demonstrations. But it was still a surprise when, on November 9 of that year, the Berlin Wall fell. (The fall was originally figurative, but the more extended process of felling the wall physically also began on that day.)
Many East Germans had been escaping to West Germany, via Hungary and Czechoslovakia. In a desperate attempt to control that emigration, the East German Communist regime decided to try a limited liberalization of travel directly from East to West Germany. Under that plan, emigrants would still need the regime's permission to cross the border.
But a party spokesman bungled the announcement on TV. East Germans who had been led to believe that emigration had become totally free, thronged to border crossing points.
Border guards, unable to get clear orders from the disintegrating government hierarchy, were faced with a dilemma. They had to either use force against those trying to cross the border, thereby escalating the violence that had taken place at the Wall since it was built in 1961, or allow free emigration. Under the circumstances, they had more to lose if they used force, than if (as was the case) they stood by and watched the exodus.
After 44 years of cold war centered on Berlin, one of the most important events in the West's victory happened accidentally. (See this recent Time report, for some revisionist history on that.) But, that's not to say that, if the government's announcement had been made more clearly, the Berlin Wall would still be standing today. The way the events played out that day is proof of how weak the East German regime had become. It could not have lasted much beyond November 9, in any case.
A few days later, the government made the anti-climactic announcement that multi-party elections would be held in 1990.
And the title of this post? Tom Friedman, in his book The World is Flat, notes how appropriate it is, that the date of the Berlin Wall opening is the opposite of the date of Al Qaeda's attacks on New York and Washington. On 11/9, the world was further opened up to globalization, and an attempt to shut globalization down happened on 9/11.