From the point of view of western self-esteem, 1989 is a year to die for: a tale of the triumph of individual freedom and the defeat of an ideological competitor, all captured live on television in the ritual destruction of a reviled enemy symbol in the heart of Europe. So the blanket coverage of the anniversary of the fall of the wall, and the parade of platitude-mouthing politicians in Berlin to mark the implosion of European communism it symbolised, was only to be expected.

What has been more striking, though, has been the lack of ideological confidence and enthusiasm that would have been expected only a few years ago. In the rest of what was eastern Europe, there have been barely any high-profile celebrations of the wider collapse of the old regimes. Given the eruption of wars, global insecurity and now economic crisis that have marked the 20 years since the end of the cold war, the larger narrative of peace, capitalist prosperity and the end of history peddled in the wake of 1989 just seems ridiculous.

For Germans, of course, the destruction of the wall didn't only signal the end of authoritarian rule and travel restrictions in the east, competitive elections and better consumer goods, as elsewhere in the former eastern bloc. It also meant an end to the militarised division of families, their capital city and an entire nation, so they have more reason to celebrate than most.

But the question in 1989 wasn't whether the old system had to change; it was how it would change. The political force that had turned the Soviet Union into a superpower, industrialised half of Europe and sent the first human being into space had exhausted itself. There were, however, alternative routes out of its crisis. What the protesters in first Gdansk and then Leipzig were mostly demanding was not capitalism, of course, but a different kind of socialism. Even given a restoration of capitalism, there were softer landings that could have been negotiated by Mikhail Gorbachev and guaranteed by the United States and its allies.

Instead, 1989 unleashed across the region and then the former Soviet Union free-market shock therapy, mass robbery as privatisation, vast increases in inequality, and poverty and joblessness for tens of millions. Reunification in Germany in fact meant annexation, the takeover and closure of most of its industry, a political purge of more than a million teachers and other white-collar workers, a loss of women's rights, closure of free nurseries and mass unemployment – still double western Germany's rate after 20 years.

And east Germany has done far better than the rest. Elsewhere in eastern Europe, the crisis created under western tutelage and nomenklatura capitalism was comparable to the Great Depression in the US, and national income took more than a decade to recover. In Russia itself, post-communist catastroika produced the greatest economic collapse in peacetime in modern history. Mortality rates rose steeply across the region in the 1990s – in Russia, the market experiment produced more orphans in the 1990s than the country's 20m wartime deaths, while Gorbachev's democratisation went into reverse.

Now, after a decade of profoundly unequal economic recovery, eastern Europe has once again been plunged into deep crisis by the west's own meltdown, with ethnic violence spreading and public sector workers facing wage cuts of up to 40%.

The western failure to recognise the shocking price paid by many east Europeans for a highly qualified freedom – the Economist this week dismissed them as "the old, the timid, the dim" – is only exceeded by the refusal to acknowledge that the communist system had benefits as well as obvious costs. The German Democratic Republic was home to the Stasi, shortages and the wall, but it was also a country of full employment, social equality, cheap housing, transport and culture, one of the best childcare systems in the world, and greater freedom in the workplace than most employees enjoy in today's Germany.

Along with the humiliation of the takeover, that's why Der Spiegel this year found that 57% of eastern Germans believed the GDR had "more good sides than bad sides", and even younger people rejected the idea that the state had been a dictatorship. Just as only one in five Hungarians believes that the country has changed for the better since 1989, only 11% of Bulgarians think ordinary people have benefited from the changes and most Russians and Ukrainians regret the disintegration of the Soviet Union.

This two-sided, Janus-like nature of 1989 is also reflected in its global and ideological impact. It kicked off the process that led to the end of the cold war. But by removing the world's only other superpower from the global stage, it also destroyed the constraints on US global power and paved the way for wars from the Gulf and Yugoslavia to the invasions of Iraq and Afghanistan.

At the same time, by destroying its main ideological competitor, 1989 opened the door to a deregulated model of capitalism that has wreaked social and economic havoc across the world for two decades. That, in turn, led to the economic crisis of 2009, which has so palpably discredited the neoliberal model. It also created the conditions for the wave of progressive change in Latin America that has challenged the post-89 social order and raised the possibility of a new form of socialism for the 21st century.

It's often said that the collapse of European communism and the Soviet Union has destroyed the only systemic alternative to capitalism. But the pressure for a social alternative has always come from capitalism itself and its failures, which are once again obvious to people throughout the world. Only 11% of those questioned in a BBC poll across 27 countries this week said they think free-market capitalism is working well, nearly a quarter believe it is fatally flawed and most want more public ownership and intervention in the economy.

The system that collapsed two decades ago, with all its lessons for the future, both negative and positive, is history. But that new movements and models will emerge to challenge a global order beset by ecological and economic crisis seems certain. As communists learned in 1989, and capitalism's champions are discovering now, nothing is ever settled.