The first stop on President Bush's European trip this week is Berlin - the capital of a united Germany. Its a fitting start for a journey which will focus on the evolving relationship between former Cold War foes.
There is perhaps no greater symbol of the Cold War than the Berlin Wall.
It was the great barbed wire and concrete divide between east and west, splitting a city, a country and a continent in two.
American presidents saw the wall as an ugly scar through Berlin, a city carved into communist and western sectors. In June 1963, John Kennedy went to West Berlin and in a display of solidarity that "today, in the world of freedom the proudest boast is 'ich bin ein Berliner'" - I am a Berliner.
24 years later, it was Ronald Reagan who went to Berlin, stood at the Brandenberg Gate and challenged Soviet Leader Mikhail Gorbachev to "tear down this wall."
In time, it is said, the division collapsed of its own weight as Communist governments fell across eastern europe and the Soviet Union became a set of newly independent states. The evolution of the post cold war world had begun.
That evolution is the underlying theme of President Bush's european tour. From once-divided Berlin he will travel to Russia where he will sign an arms reduction pact and discuss further cooperation with President Vladimir Putin. He will end his trip near Rome, as NATO marks the start of a new agreement to work with the Russians.
It's an evolution that George W. Bush said he never imagined as he grew up at the height of the Cold War. During his last public appearances with President Putin - this one at a school near the Bush family ranch in Texas - he marveled at the change. "I bet a lot of folks here, particularly the older folks, never dreamt that an American president would be bringing the Russian president to Crawford, Texas," he said. "A lot of people never really dreamt that an American president and a Russian president could have established the friendship that we have."
There are indications Mr. Bush may find a greater meeting of the minds in Moscow than he encounters in his talks with leaders in Berlin, Paris and Rome, where there are frictions over trade and next steps in the war on terrorism. The strategic arms reduction agreement he will sign in Moscow is yet another sign of a growing relationship that has been described by officials as perhaps the biggest development of the Bush administration.
White House National Security Advisor Condoleezza Rice acknowledges the treaty won't make the headlines that such an agreement might have made in years past. But she says that may be a very good sign. "What keeps Russia and the United States from going to war today is not the number of nuclear weapons that they have on either side or the anti-ballistic missile treaty, or some outdated notion of strategic stability," she said. "It is that they have nothing to go to war about."
President Bush will not ignore the past during his trip, particularly during a visit to France and the graves of American servicemen who died in World War II. But his focus is likely to be on the future as he signs agreements that solidify ties between former enemies, and tours a Europe that is "whole, free, and at peace."