WASHINGTON - After eight years of the closest possible relations, the United States and Israel may be headed for a period of increased strain, particularly as it appears likely that whatever Israeli government emerges from last week's election will be more hawkish than its predecessor.
Iran, with which President Barack Obama has pledged to engage in a "constructive dialogue", and the future of its nuclear program will no doubt be the greatest source of tension between the two allies. The new president's commitment to achieving real progress on a two-state solution to the Israel-Palestinian conflict may also provoke serious friction.
This will particularly be the case should a reunified Arab League launch a major new push for the adoption of its 2002 peace plan, which provides for Arab recognition of Israel in return for the latter's withdrawal from all occupied Arab lands.
Last week's election produced a clear majority for right-wing parties led by the Likud Party of former prime minister Binyamin Netanyahu, who has repeatedly declared his opposition to a settlement freeze, territorial concessions and the creation of a viable Palestinian state.
With the endorsement of Avigdor Lieberman, whose party, Israel Our Home, came a strong third in last week's general elections, Netanyahu appears increasingly likely to become prime minister.
Even if the more-centrist Kadima leader, Foreign Minister Tzipi Livni, can patch together a government of national unity, the right-wing parties will be able to effectively block major concessions in any peace talks, in the absence of any external pressure.
"Given the philosophical differences between Kadima and Likud on peace issues, such a unity government would be hard-pressed to make the historic decisions needed to reach a deal with the Palestinians," wrote former US Middle East peace negotiator, Aaron David Miller, in the Jewish publication Forward this week.
But Obama and his Middle East Special Envoy George Mitchell may indeed be willing to exert pressure on Israel - among other things, by tabling their own views about a final peace agreement and how precisely it might be achieved - especially if ongoing Arab efforts to reconcile Hamas and Fatah in a new coalition government succeed.
If all goes well on that front, the Arab League, fortified by a developing rapprochement between Syria and Saudi Arabia, could announce the latest version of its 2002 peace plan at next month's summit in Doha, according to Marc Lynch, a George Washington University specialist on Arab politics.
Such a move "could galvanize the situation and put the onus on whatever Israeli government emerges to respond positively", he wrote on his widely read blog on the Foreign Policy website this week.
"If you have a unified Palestinian government and a unified Arab move for peace," added Daniel Levy, a former Israeli peace negotiator, "then it's much more likely that Obama will step up his own efforts - ideally, working with an Israeli government that's ready to go along with a serious peace process, but, if not, being willing to make his disagreement [with that government] known."
The result could be a serious test between the next Israeli government and its influential US advocates. The Obama administration clearly believes that real progress toward resolving the 60-year-old conflict is critical both to restoring Washington's credibility among the Arab states and curbing the further radicalization of the region's population - particularly in the wake of Israel's recent military offensive in Gaza.
A more likely source of tension between the US and Israel, however, will be Iran's nuclear program.
"It's very important to realize that Iran is going to be the most likely issue on which Israel and the United States will have a serious difference of opinion, if not a confrontation, in the next year," warned former US ambassador Samuel Lewis after the Israeli elections.
Although Netanyahu has been the most outspoken, virtually the entire Israeli political and military establishment has described Iran's alleged nuclear ambitions as an "existential" threat to the Jewish state. They have suggested that Israel should be prepared to unilaterally attack Tehran's key nuclear facilities as early as next year if it cannot persuade Washington to do so.
Already last year, Prime Minister Ehud Olmert asked former president George W Bush for bunker-busting bombs, refueling capacity and permission to fly over Iraq for an attack on Iran, according to a new book by New York Times correspondent David Sanger, entitled Inheritance.
That request was strongly opposed by Pentagon Chief Robert Gates, who has been retained by Obama, and ultimately rejected by Bush. According to Bush's former top Middle East aide, Elliott Abrams, Bush - who almost never denied the Israelis anything - was worried that any attack on Iran risked destabilizing Iraq.
While the violence in Iraq has continued to decline, US military commanders insist that stability there remains "fragile", so Bush's concerns about the implications for Iraq of a US or Israeli attack on Iran are likely to be shared by Obama.
Even more important, however, is the new administration's conviction that Afghanistan and Pakistan - which, like Iraq, also border Iran - constitute the true "central front in the war on terror". This assessment was backed up by Obama's announcement this week that he will deploy 17,000 more US troops to Afghanistan over the next few months, bringing the total US and North Atlantic Treaty Organization (NATO) troop strength there to some 80,000.
Top US civilian and military officials dealing with "AfPak", as the new administration has dubbed the two countries, have made clear that they hope to enlist Iran, with which Washington cooperated in ousting the Taliban in 2001, in helping to stabilize Afghanistan.
''It is absolutely clear that Iran plays an important role in Afghanistan," Obama's Special Envoy to Afghanistan and Pakistan, Richard Holbrooke, said in Kabul earlier this week in an interview during which he pointedly declined to repeat Bush administration charges that Tehran was aiding the Taliban. "[Iran has] a legitimate role to play in this region, as do all of Afghanistan's neighbors," he insisted.
Most regional specialists, including Bruce Riedel, who co-chairs the White House's "AfPak" policy review, and John Brennan, Obama's top counter-terrorism adviser, have long argued that Iran's cooperation would make Washington's effort to stabilize the region and ultimately defeat al-Qaeda markedly easier while, conversely, its active opposition, as in Iraq, is likely to make the task considerably more difficult.
That assessment has, if anything, gained strength in just the past few weeks as Washington has scrambled to secure new supply lines into land-locked Afghanistan after a key bridge in Pakistan's Khyber Pass was destroyed by Taliban militants there and Kyrgyzstan threatened to end Washington's access to its Manas air base.
While US efforts to compensate have focused so far on the overland route through Russia and the Central Asian "Stans", a growing number of voices have noted that a much less costly and more efficient alternative route would run from Iran's southern ports into western Afghanistan.
Although Tehran would no doubt be very reluctant to permit the US military to use its territory at this point, NATO's supreme commander, US General John Craddock, said earlier this month that he had no objection if other NATO members could negotiate an access agreement with Iran.
Of course, it is not yet clear whether US success in "AfPak" - and Iran's possible role in securing it - will help trump Washington's concerns about Tehran's nuclear ambitions.
But the clear priority stabilizing Southwest Asia is being given by the new administration, and the abrupt change in the rhetoric emanating from Washington about Iran - not to mention abiding concerns regarding Iran's ability to destabilize Iraq - clearly run counter to Israel's efforts to depict Tehran's nuclear program, as in Netanyahu's words, "the greatest challenge facing the leaders of the 21st century ... ".
Obama will surely make it more difficult for Netanyahu or anyone else in the next Israeli government to "harness the US administration to stop the threat".
Jim Lobe's blog on US foreign policy can be read at http://www.ips.org/blog/jimlobe/. (Inter Press Service)