Bush was greeted at the airport in Tel Aviv on January 9 by a military band and dozens of dignitaries, including Israeli President Shimon Peres and Prime Minister Ehud Olmert.
In brief remarks at the welcoming ceremony, Bush said he saw a "new opportunity" for peace between Israelis and Palestinians.
"We seek lasting peace," Bush said. "We see a new opportunity for peace here in the Holy Land and for freedom across the region." Bush said he expected to "discuss our deep desire for security, for freedom, and for peace throughout the Middle East" in talks with Peres and Olmert.
Bush's agenda then takes him to a separate meeting with Palestinian Authority President Mahmud Abbas in Ramallah on January 10.
One of the aims of Bush's trip is to spur peace negotiations that were relaunched two months ago, at an international conference Bush hosted in Annapolis, Maryland. There, Israeli and Palestinian leaders pledged to work toward a peace deal by the time Bush leaves office in January 2009. But negotiations since then have bogged down.
In his comments, Peres said the coming year would be a "moment of truth" for Middle East peace.
Peres also touched on another issue looming large over Bush's trip: Iran's activities and influence in the region. The Israeli president called on Bush to help stop what he called the "madness" of Iran, Hamas, and Hizballah: "We take your advice not to underestimate the Iranian threat. Iran should not underestimate our resolve for self-defense."
Bush's trip also takes him to key allies in the Persian Gulf, starting with Kuwait on January 12.
Before departing Washington, Bush said he would be reminding Washington's friends in the region that Iran remains a threat, regardless of what he called the "mixed signal" sent by a recent U.S. National Intelligence Estimate that suggested Iran had suspended its nuclear-weapons program in 2003.
"One of the problems we have is that the intelligence report on Iran sent a mixed signal," Bush said. "And I'm going to remind them what I said in that press conference when I sat there and answered some of your questions: Iran was a threat, Iran is a threat, and Iran will continue to be a threat if they are allowed to learn how to enrich uranium."
The United States is eager to curb Iran's nuclear ambitions, which have sparked fears of a possible nuclear arms race in the volatile region if Arab states respond to the specter of a nuclear-armed Iran with programs of their own.
Meanwhile, the leaders of neighboring Sunni Muslim countries have expressed concern about Shi'a-dominated Iran's recent effort to accumulate influence in the region.
"This is a double-edged sword," Murhaf Jouejati, a professor of Middle East studies at the National Defense University in Washington, told RFE/RL. "The Sunni Middle East is very fearful of Iran, but at the same time, I think they would rather not have any American action against Iran, which will exacerbate the situation and put them immediately on the front line."
Jouejati says of Iran's neighbors that "what they would like to see is a wise and judicious policy toward Iran, and one also that calms its hegemonic ambitions."
A Fine Line
Bush will have to walk a fine line between maintaining a strong stance against Iran's nuclear program and reassuring Sunni leaders friendly to the United States, according to Michael O'Hanlon, a foreign affairs expert at the Brookings Institution in Washington.
O'Hanlon says he expects Bush might respond favorably to what many see as a decline in Iran's involvement in the sectarian violence in neighboring Iraq. "Mr. Bush will probably want to show a little bit of restraint to reciprocate [for] whatever restraint Iran might be showing right now inside Iraq," O'Hanlon says. "It's a funny sort of game to play where you've got a fairly strong conviction [that] Iran's a big problem -- enduring issues, obviously, over their nuclear program, their support for terrorism and their role in Iraq -- and yet some hopefulness that they are deciding themselves to scale it back in Iraq, a trend that, if true, we certainly would not want to jeopardize."
But O'Hanlon was quick to add that Bush might prove him wrong and might even speak out openly against Iran during the trip as a way to ensure nervous Sunni countries that the United States won't allow Iran to gain predominance in the region.
"I don't think that [the U.S. government is] going to be looking to make nice towards Iran on this trip," O'Hanlon says. "I think that, on balance, the nuclear program is still a problem, Iran's support for Middle East terror is still a problem, and Iran's role in Iraq is still a problem. And on balance, the overall situations are still more bad than good, but some of the recent trend lines have shown a little bit of alleviation of our worst-case worries."
U.S.-Iranian tensions were highlighted by an incident in the Strait of Hormuz on January 6, when U.S. officials have accused Iranian speedboats of "a very provocative act" that "came very close to resulting in an altercation between our forces and their forces," in the words of White House national security adviser Stephen Hadley.
"It's a warning to them," Hadley added aboard Air Force One as it carried Bush to Tel Aviv, "They've got to be very careful about this, because if it happens again, they are going to bear the consequences of that incident."
Iran's state-run, English-language Press TV accused the United States of presenting "fabricated" video and audio recordings that purport to show small Iranian boats swarming around U.S. warships.
Iranian Defense Minister Mostafa Mohammad-Najjar dismissed Western reports of the incident, the Fars news agency reported, saying Iran's naval units were carrying out "routine" operations in the strait and accusing U.S. officials of trying to stoke fears of Iran among its neighbors.
Iran's Foreign Ministry has already criticized Bush's Middle East trip as a "propaganda" effort designed to "interfere" in relations among regional states.
Bush's trip is scheduled to end in Egypt on January 16.
THE COMPLETE PICTURE: RFE/RL's complete coverage of controversy surrounding Iran's nuclear program.
An annotated timeline
of Iran's nuclear program.