The following op-ed piece by Green Cross International's Founding President Mikhail Gorbachev appeared The Times on Monday 9 November:

 

The German people, and the whole world alongside them, are today celebrating a landmark date in history: the 20th anniversary of the fall of the Berlin Wall.

 

Not many events can claim their place in the collective memory as a watershed that divides two distinct periods. The dismantling of the Berlin Wall - that stark, concrete symbol of a world divided into hostile camps - is such an event. It brought incredible hope and opportunity to people everywhere, and provided the 1980s with a truly jubilant finale. That is something to think about as this decade draws to a close, and the chance for humanity to take another momentous leap forward appears to be slipping away.

 

The road to the end of the Cold War was certainly not easy, or universally welcomed at the time, but it is for just this reason that its lessons remain relevant. In the 1980s the world was at an historic crossroad. The arms race had created an explosive situation. Nuclear deterrents could have failed at any moment. We were heading for disaster, spending billions on an arms race, rather than investing in creativity and people.

 

Today another planetary threat has emerged. The climate crisis is the new wall that divides us from our future, and today's leaders are vastly underestimating the urgency, and potentially catastrophic scale, of the emergency.

 

People used to joke that we will struggle for peace until there is nothing left on the planet; the threat of climate change makes this prophecy more literal than ever. Comparisons with the period immediately before the Berlin Wall came down are striking.

 

Like 20 years ago, we face a threat to global security and our very future existence that no one nation can deal with alone. And, again, it is the people who are calling for change. Just as the German people declared their will for unity, world citizens are today demanding that action is taken to tackle climate change and redress the deep injustices that surround it. Twenty years ago key world leaders demonstrated resolve, faced up to opposition and immense pressure, and the Wall came down. It remains to be seen whether today's leaders will do the same.

 

Addressing climate change demands a paradigm shift on a scale akin to that required to end the Cold War. But we need a "circuit-breaker" to escape from the business-as-usual that currently dominates the political agenda. It was the transformation brought about by perestroika and glasnost that provided the quantum leap for freedom for the Soviet Union and Eastern Europe, and opened the way for the democratic revolution that saved history. Climate change is complex and closely entwined with a host of other challenges, but a similar breakthrough in our values and priorities is needed.

 

There is not just one wall to topple, but many. There is the wall between those states which are already industrialised, and those developing countries which do not want to be held back. There is the wall between those who cause climate change, and those who suffer the consequences. There is the wall between those who heed the scientific evidence, and those who pander to vested interests. And there is the wall between the citizens who are changing their own behaviour and want strong global action, and the leaders who are so far letting them down.

 

In 1989, incredible changes that were deemed impossible just a few years earlier were implemented. But this was no accident. The changes resonated the hopes of the time and leaders responded. We brought down the wall in the belief that future generations would be able to solve challenges together. Today, looking at the cavernous gulf between rich and poor, the irresponsibility that caused the global financial crisis, and the weak and divided responses to climate change, I feel bitter. The opportunity to build a safer, fairer and more united world has been largely squandered.

 

To echo the demand made of me by my late friend and sparring partner President Reagan: Mr Obama, Mr Hu, Mr Singh, Mr Brown and, back in Berlin, Ms Merkel and her European counterparts: "Tear down this wall!"

 

For this is Your Wall, your defining moment. You cannot dodge the call of history. I appeal to heads of state and government to personally come to the climate change conference in Copenhagen this December and dismantle the wall. The people of the world expect you to deliver; do not fail them.

 

Mikhail Gorbachev, former President of the Soviet Union, was awarded the 1990 Nobel Peace Prize for his role in the peaceful conclusion of the Cold War. He is the Founding President of Green Cross International and is heading an international Climate Change Task Force.