Former U.S. President George Bush delivers a speech at a special Bundestag assembly, to commemorate ten years since the fall of the Berlin Wall. The day before, George Bush was awarded the honorary citizenship of Berlin in Berlin's town hall.

Former German chancellor Helmut Kohl, former Soviet leader Mikhail Gorbachev, center, and former U.S. President George Bush (right) sign a piece of the Berlin wall Monday. George Bush marked the 10th anniversary celebrations of the collapse of the Berlin Wall by saying it was the chemistry of world leaders that helped to bring east and west together a decade ago.