The question is, what sort of presumptive Democratic candidate will his domestic audience see? Will it be someone reminiscent of John F. Kennedy – cool, articulate, and the center of cheering foreign crowds?
Or will it be a traveler more like candidate Jimmy Carter – an inexperienced, provincial politician on a learning tour?
For the Illinois senator, the inherent risks in his travel are intensified by the fact that he will visit the Middle East, a place where, for American politicians, every word counts and the smallest misstep can become a huge gaffe.
"For Obama this trip is essential," says Larry Sabato, director of the Center for Politics at the University of Virginia in Charlottesville. "If anything trips him up, other than race, it is going to be his lack of foreign experience."
Next week, Senator Obama is scheduled to travel to Europe, Israel, and the West Bank. Many details of the trip have been kept secret for security reasons, but he is expected to meet with both Israeli Prime Minister Ehud Olmert and Palestinian Authority President Mahmoud Abbas. In Berlin, he will deliver what his aides are billing as a major address on transatlantic relations.
On July 15, Obama reiterated his vow to withdraw US combat troops from Iraq within 16 months of becoming president, and said that if he were elected, Al Qaeda and Afghanistan would be his top foreign-policy priorities.
"By any measure, our single-minded and open-ended focus on Iraq is not a sound strategy for keeping America safe," said Obama in a speech at the Ronald Reagan Building and International Trade Center in Washington.
Presumptive GOP nominee Sen. John McCain criticized his rival for making a speech on strategy for Iran and Afghanistan before actually traveling to those countries. Obama has never been to Afghanistan, Senator McCain noted.
"In my experience, fact-finding missions usually work best the other way around: First you assess the facts on the ground, then you present a new strategy," said McCain prior to addressing a town hall meeting in Albuquerque, New Mexico.
Right now the US public appears evenly split on the question of whether Obama would be a good commander in chief. According to a new Washington Post/ABC News poll, 48 percent of respondents said that Obama would be an effective leader of the military. Forty-eight percent said that he would not.
On policy for Iraq in particular, 47 percent of respondents said they would trust McCain more to handle the war. Forty-five percent picked Obama.
Thus Obama's coming trip could be a crucial way for the candidate to bolster his international credentials and draw distinctions with the current administration and his rival McCain, say political experts.
Images of a rapturous reception could help. Obama is a subject of intense interest overseas, and all signs point to a turnout of large crowds to greet him in Europe. John F. Kennedy, as both a candidate and chief executive, was greatly bolstered at home by similar turnout.
"It's not like Americans will base their voting judgment on what foreigners think. But the contrast with the current administration could convey the sense that the world would work with the US [if Obama wins]," says Norman Ornstein, resident scholar and political expert at the American Enterprise Institute in Washington.
Obama has also been fortunate in that events in Afghanistan appear to have borne out his prediction that the administration has focused too much on Iraq, says Mr. Ornstein.
For US troops, Afghanistan is now deadlier than Iraq. The Bush administration may be mulling a withdrawal of troops from Iraq for the purpose of bolstering forces in Afghanistan.
"It allows Obama to say 'I told you so,' " says Ornstein.
However, Obama has already fallen prey to something that has long bedeviled US politicians inexperienced on the international stage: the gaffe about the Middle East.
Last month, at a conference of the American Israel Public Affairs Committee, Obama endorsed the two-state solution to the Israeli-Palestinian conflict, and then added that Jerusalem should remain undivided and the capital of Israel.
Palestinian Authority President Abbas reacted angrily to that statement, and Obama has since amended it, saying that he only wants no barbed wire to divide Jerusalem in two.
"I was not trying to predetermine what are essentially final status issues," said Obama in a broadcast interview with columnist Fareed Zakaria.
Such missteps might remind older US voters of Jimmy Carter as a presidential candidate, says Mr. Sabato of the University of Virginia. Though Carter today is renowned for his world travel, when he ran for president he was a Georgia governor without extensive international experience.
Obama's itinerary might reinforce this naïve image, says Sabato.
"I'm surprised it's not more extensive," he says. "It's almost a remedial trip."