Energy crisis - World faces its biggest challenge

This week much of Europe has been celebrating the 20th anniversary of the fall of the Berlin Wall. In time it could well be considered as one of greatest seminal moments in world history, akin to the impact of the French Revolution, which began with the fall of the Bastille in 1789.

Both events were largely symbolic. “The fall of the Berlin Wall brought hope and opportunity to people everywhere,” Mikhail Gorbachev writes today. He is the man who will forever be most associated with the event, because he essentially allowed it to happen.

Today he is writing in his new capacity as the founding president of Green Cross International, he is heading the International Climate Change Task Force. He recalls that moment in June 1987 when President Ronald Reagan stood at the Berlin Wall and challenged him to “tear down this wall”.