The "wink" the United States has given Israel in the wake of its assassination of the spiritual leader of Hamas, or the Islamic Resistance Movement, exemplifies once again how successful Israel has been at aligning its fight against militant Palestinians with the US war on terror.
At the same time, the apparent tacit US approval - which contrasts with the swift condemnation of the killing by other countries - suggests why the road ahead in the Middle East remains so arduous for the US.
What looks to Arabs in the region like a US "green light" to Israel also raises the prospect that the US, or at least American interests in the region, will become a target of militant Palestinian reprisal.
"The Zionists didn't carry out their operation without getting the consent of the terrorist American administration, and it must take responsibility for this crime," Hamas reportedly said in a statement Monday.
That may not portend attacks in the US, experts on the region say, but it does suggest how the deteriorating Israeli-Palestinian situation may have growing impact on the US-led war on terror.
"Hamas is not about to shift the focus of its actions to the US, although Americans in the vicinity could be targeted as we've seen in the past," says William Quandt, a Middle East expert at the University of Virginia and a former National Security Council official. "But with less centralized control over the militants as the leadership is affected, we could see something emerge more like Al Qaeda, with a proliferation of more or less affiliated groups that add this kind of [assassination] to their list of grievances against the US."
As for whether the US had probably received advance notification of Israel's act, Mr. Quandt says, "There isn't any need to be consulted. The US is in a position of having opened the door without having specifically given the green light, and [Israeli Prime Minister Ariel] Sharon has become very adept at telling the US, 'We're doing exactly what you are doing' " in fighting terror.
National Security Adviser Condoleezza Rice said Monday that there had been no discussion between President Bush and Mr. Sharon about the plan, which resulted in an Israeli helicopter gunship killing Sheikh Ahmed Yassin as he left dawn prayers.
But in an appearance on NBC's "Today" show, Dr. Rice added, "Let's remember that Hamas is a terrorist organization and that Sheikh Yassin has himself, personally we believe, been involved in terrorist planning."
The killing - which the Israeli government had openly said would be pursued after an earlier attempt on the sheikh's life failed last September - was strongly denounced by European foreign ministers meeting Monday in Brussels. The assassination "is unacceptable," said British Foreign Secretary Jack Straw. "It is unjustified, and it is very unlikely to achieve its objectives."
That difference in response is an example of why the US, despite its goal of championing reform and development in the Middle East, remains in such low esteem and is so mistrusted among Arabs. The US is seen as so unequivocally on Israel's side in the Arab-Israeli conflict - and even more so in an election year - that acts such as the Yassin killing only reconfirm perceptions the US is no longer the "honest broker" it once was in the region.
Yet negotiations in the Israeli-Palestinian conflict were going nowhere, with or without America's good auspices, some experts believe. They say the two sides have become stuck in a syndrome of attack and reprisal that leaves little hope for progress in the near term.
"The situation is going to be worse for a while, as the pattern of revenge attacks we've seen in the past is carried out following this [Yassin killing], and it will stay that way as long as the Palestinians stick to this phase of trying to advance through acts of terrorism," says James Phillips, a Middle East specialist at the Heritage Foundation in Washington.
Others say Hamas's vow for revenge highlights the need for the US to remain focused on the forces of terrorism that have proved to be its central enemies.
"This only underscores the paramount importance of the US focusing its terrorism efforts on Al Qaeda and not conflating the threat to include other terrorist groups - such as Hamas - who do not attack the United States," says Charles Peña, director of defense policy studies at the Cato Institute in Washington. "This in no way justifies Hamas's or any other anti-Israeli terrorism, but simply recognizes that the US cannot afford to make other countries' terrorist threats our terrorist threat."
Despite Hamas's warnings, Mr. Phillips says he does not expect to see the group carry out specific attacks against the US. "I think they understand they would be worse off because of it," he says, explaining that "they would risk losing those European and other friends" who see Hamas in terms of a nationalist struggle.
Virginia's Quandt notes that the assassination was carried out with US-supplied military hardware - equipment over whose use the US by law retains some measure of control. "If we had objections as to how it's being used, the administration should have informed Congress of that," he says. The lack of any such objections tells Sharon his equating of the Palestinian conflict with the broader US-led war on terror is a winning strategy, he says.
In this context, few observers expect much progress on what the Bush administration says are its broader goals for the region. "Conditions weren't ripe for anything going forward even before this [killing]," says Phillips. "So I think now the [American] strategy is to try to encourage some positive democratic reforms and economic advances elsewhere in the region that might nudge the Palestinians back to discussions and renouncing terrorism."