The president, a look of agitation having supplanted his exuberance of just a few days ago, replied angrily to yesterday's Palestinian suicide bombing in Jerusalem, which killed 17 people, including the bomber.
"It is clear there are people in the Middle East who hate peace," he told reporters during a visit to Chicago. "I strongly condemn the killings, and I urge and call upon all the free world, nations which love peace, to not only condemn the killings but to use every ounce of their power to prevent them from happening in the future."
It was the second day in a row that the president found himself condemning events in the Middle East from afar. On Tuesday, Bush rebuked Israel for attempting to assassinate a militant Palestinian leader in a missile strike - a move White House officials regarded as provocative.
Secretary of State Colin L. Powell, meanwhile, implored Israeli Prime Minister Ariel Sharon and Palestinian Prime Minister Mahmoud Abbas to stick by the "road map" to peace that each committed to follow during their summit with Bush last week in the Jordanian port city of Aqaba.
"This is the time for us to remain steadfast, to continue moving down the path that was laid out at Aqaba," Powell told reporters after meeting with United Nations Secretary-General Kofi Annan at the State Department.
Annan, echoing Powell's remarks, said "it is important that the leaders stay the course. What happened this morning is utterly reprehensible, but it should not deter the leaders from moving ahead."
The history of other American peace initiatives run aground by Palestinian-Israeli violence during the past 32 months suggests that hope may be in vain. The road map plan - which is also backed by the United Nations, the European Union and Russia - now risks failing just like its predecessors, the "Mitchell report," the "Tenet work plan" and the "Zinni plan," each named for a prominent American mediator who left the region in frustration.
The road map outlines a series of reciprocal concessions and confidence-building steps both sides are supposed to take, leading to the establishment of an independent Palestinian state by 2005.
In its initial security phase, the plan calls for the Palestinians to stop terrorist attacks against Israel and for the Israelis to ease military restrictions in the West Bank and Gaza. The Palestinians are to press ahead with political and economic reforms, while the Israelis are expected to dismantle settlement outposts built in the occupied territories since March 2001.
Militant Palestinian groups such as Hamas denounced Abbas for agreeing to the peace plan and promptly launched new attacks against Israeli targets. Israel replied by sending helicopters to fire rockets at Hamas co-founder Abdel Aziz Rantisi on Tuesday and other Hamas leaders after yesterday's suicide bombing.
Bush now faces a crucial test of his promise last week to remain directly involved in the peace process and "ride herd" on Israelis and Palestinians to abide by the road map. In practice, that will almost certainly mean pressuring Abbas to send security forces to confront Palestinian militants, where Abbas prefers to negotiate with them, and pressuring Sharon to cease targeted assassinations and improve living conditions for Palestinian civilians.
"The president put his personal commitment and prestige on the line at Aqaba," said Judith Kipper, a Middle East expert at the Center for Strategic and International Studies. "His determination is the key to whether this road map is going to live or die. The real question is whether the president is going to allow the terrorists to set the agenda at this point. He's going to have to lean on everybody."