Sen. Barack Obama's trip to the Middle East and Europe marks the Democrat's first high-profile step onto the international stage, a campaign-season audition of sorts for a presidential candidate pledging a new era in diplomacy and an end to the U.S. combat role in Iraq.
"The stakes are very high for Obama," said Lee Hamilton, president of the Woodrow Wilson International Center for Scholars and a supporter of the Illinois Democrat.
While Obama currently leads in the polls, "foreign policy is one area where they (voters) have their doubts" about him, Hamilton said.
Campaign officials have announced stops in Jordan, Israel, Germany, France and England. Obama also has pledged to travel to Iraq and Afghanistan this summer, but aides have not said whether those war zones will be part of the same trip.
The trip is planned to put Obama into settings often occupied by presidents, including formal meetings with foreign leaders, public speeches and visits to historical sites.
"It's an opportunity for him to sit down with the international leaders with whom he would have to work as president of the United States, and discuss some of the issues," said David Axelrod, the campaign's senior strategist.
Leads in many polls but not foreign policy
Obama has been critical of Bush's foreign policy in his campaign for the White House, but Hamilton said the Democratic presidential nominee-in-waiting must tread lightly. "Criticizing foreign policy in Washington in one thing. Criticizing it in Berlin" is another, he said.
"There will be a lot of eyes on him, and we know that," Axelrod said, when asked about the risk of politically damaging errors.
Less than four months before the election, Obama's trip comes at a time when he leads Republican rival John McCain in many polls but runs no better than even on many foreign policy questions.
In a recent Washington Post-ABC poll, 72 percent of those surveyed said McCain knew enough about world affairs to serve effectively as president, compared to 54 percent for Obama.
The two men were in a statistical tie when voters were asked who was more trusted to handle the situation between Israel and the Palestinians or the war in Iraq.
Whatever he says or does, Obama will be under scrutiny from Republicans eager to raise doubts about his readiness to handle foreign and defense policy.
"This trip is about politics. It's a way for Obama to try and compete on foreign policy," said Jill Hazelbaker, McCain's communications director.
McCain has left the country twice this summer, once for Canada and a second time to visit Colombia and Mexico. In both cases his principal goal was to express support for expanded trade.
At home, Obama has struggled to consolidate his support among Jewish voters wary of his commitment to Israel.
And while Obama is expected to meet with Israeli Prime Minister Ehud Ohlmert, Palestinian officials have announced he will visit the West Bank. McCain did not meet with Palestinians in his most recent visit to the Middle East in March.
"We welcome this meeting," Saeb Erekat, a Palestinian negotiator, said recently. He added that if Obama is elected "we hope he will stay the course between Israel and the Palestinians in reaching peace and a two-state solution." Bush is trying to broker a peace agreement between Israel and the Palestinians before leaving office in January.
Obama stirred controversy in June with a speech before the American Israel Public Affairs Committee in which he endorsed a two-state Israel-Palestine settlement, yet said Jerusalem should remain both the capital of the Jewish nation and undivided.
Palestinian leaders quickly rejected the statement. "...We will not accept a Palestinian state without having Jerusalem as the capital of a Palestinian state," said Mahmoud Abbas, the Palestinian president, and the next day, Obama backpedaled.
"Well, obviously, it's going to be up to the parties to negotiate a range of these issues. And Jerusalem will be part of those negotiations," he said in a CNN interview. He added that "as a practical matter, it would be very difficult to execute" a division of the city.
Stops in Western European capitals are standard for U.S. politicians seeking to burnish foreign policy credentials, and Hamilton said government leaders are eager to meet the candidate.
Campaign aides have disclosed almost nothing of the European itinerary.
Controversy preceded Obama to Germany when aides sought to use the Brandenburg Gate in Berlin as the site for a speech.
Chancellor Angela Merkel was less than enthusiastic, dispatching spokesman Thomas Steg to say she had "only limited understanding for using the Brandenburg Gate as an election campaign backdrop, as it were, and has expressed skepticism about pursuing such plans."
Obama's campaign spokesman Bill Burton responded that the Illinois senator has "considered several sites for a possible speech, and he will choose one that makes most sense for him and his German hosts."
Constructed in 1791 as a symbol of peace in Germany, the gate stood for 28 years during the Cold War at the heavily fortified Berlin Wall that blocked off communist East Germany's sector of the divided city. Probably the capital's best-known monument, it has been restored as a national symbol for a reunified Germany.
On Friday, Merkel's spokesman Ulrich Wilhelm said the German leader will welcome U.S. presidential hopeful Barack Obama to her office in Berlin.