Not only has President Barack Obama inherited a disastrous economic and financial situation from George W. Bush, as well as two unfinished wars in Iraq and Afghanistan but he must now also wrestle with an Israeli ally which, having long been pampered and indulged by Bush, has now lurched dangerously to the ultra-nationalist Right - in paranoid defiance of much of the world.

Last Tuesday's Israeli elections have dealt a serious blow - perhaps a fatal one - to the prospects for Arab-Israeli peace. They have also thrown up a major obstacle in the way of Obama's policy of building bridges to the Arab and Islamic world.

The election results have raised the distinct possibility of a battle of wills between Obama and Benjamin Netanyahu, leader of Israel's Likud party who, at the head of a right-wing "national bloc" of some 65 Knesset members, is the clear front-runner for prime minister. In such a battle, it is by no means certain that Obama will emerge victorious.

The US-Israeli relationship has never simply been one between a superpower patron and a client state. The relationship is a feature of US domestic politics rather than of foreign policy. More often than not, the tail has wagged the dog. In defence of what it saw as its vital interests, Israel has never hesitated to manipulate, coerce, spy on and even threaten its patron. In a celebrated case, dating back to 1967, Israel even went so far as to attack and cripple the USS Liberty, an American electronic surveillance ship, when it thought that US monitoring might set a limit to its conquests.

In any event, Israel has spent decades preparing for just such an emergency as it now faces - the election of a US President who might attempt to be even-handed in the Middle East. Netanyahu will be reluctant to clash head-on with the American President. He knows how dependent Israel is on the United States - in every field from armaments and advanced technology to finance and diplomacy. But he can be counted on to use every trick in the book to limit what Obama can realistically accomplish in the Middle East. He will not hesitate to mobilise Israel's many US assets, including the wall-to-wall support for the Jewish state in the US Congress.

On the Israeli political scene, Netanyahu's only serious rival is Tzipi Livni, head of the centrist Kadima party. But she can at best put together a coalition of some 55 members, far short of the minimum 61-seats necessary for a majority in the 120-seat Knesset. Her chances of forming a governing coalition are, therefore, virtually nil. The next four to five weeks will see the usual horse-trading, as the myriad small Israeli parties, each representing special interests, barter their seats for benefits. It seems almost certain that President Shimon Peres will have no choice but to ask Netanyahu to form a government.

Ehud Barak and his Israeli Labour Party are the big losers of the elections. Labour - the Zionist architect of the Israeli state, which ruled for nearly 30 years from 1948 to 1977 - won only 13 seats. It must now rebuild itself in opposition. The far left Meretz, the only party which campaigned for peace with the Palestinians, won a mere three seats. Nothing could better illustrate Israel's rejection of peace.

Where does this leave America? Obama has pledged to bring peace to the Middle East. He and his Secretary of State, Hilary Clinton, have made it clear that their preferred formula is a two-state solution, that is to say - in the time-honoured phrase - a Palestinian state living side by side with Israel, in peace and security. George Mitchell , Obama's special envoy to the Middle East, is the human embodiment of this policy. Peace is also the fervent wish of the international community - of the European Union, of the Arab states, of Russia, of Turkey, of the UN Secretary General Ban Ki-moon.

It must be assumed that Netanyahu will do everything possible to frustrate Obama's objective. He has declared explicitly that he rejects the very principle of "land for peace". He is opposed to any territorial concession, whether to the Palestinians or to Syria. He refuses even to discuss the question of occupied Jerusalem. Last week, he planted a tree on the Golan Heights to signal that Syria's plateau was to be Israel's forever.

Netanyahu's main ally is the far-right, Arab-hating Avigdor Lieberman, head of Yisrael Beiteinu (Israel our home), who wants to expel those Palestinians of 1948 areas (Israeli Arabs) who refuse to pledge loyalty to the Jewish state. He has been promised an "important ministry" in any future Netanyahu administration.

Why have Israelis voted this way? Many commentators point to the impact on Israeli opinion of the rockets Hamas has fired at Israel's Negev towns. They cause little damage and claim few victims, yet they keep the population in a state of nervous and angry alert. The Gaza War was clearly another factor, satisfying the Israelis' need for a demonstration of overwhelming force. It would seem that Israeli opinion is afraid - afraid of enemies abroad and afraid of enemies within, that is to say the 1.2 million Israeli Arabs, whom racists like Lieberman depict as a fifth column. Difficult as it is for the world to understand, Israel has worked itself up into a state of hysteria about the alleged threat from Iran, and from Hezbollah and Hamas.

Israel attempted to destroy Hezbollah in 2006 (killing 1,200 Lebanese in the process) and then Hamas last December-January (killing 1,300 Palestinians.) In both cases, its ferocious military machine, deployed in total disregard of the civilian population, was of no avail. Hezbollah and Hamas not only survived, but emerged stronger, politically if not militarily.

As for Iran, the Israelis have persuaded themselves that its nuclear programme poses an "existential" threat, even though, with an arsenal of more than 200 nuclear warheads and the systems to deliver them, Israel could easily "wipe Iran off the map", if a credible threat were ever to materialise from that direction. Israelis are deeply worried that Obama's overtures to Iran will allow the Islamic Republic to proceed with its nuclear programme.

Israeli fears are profoundly irrational. No doubt they are a product of the memory of the Holocaust. But they are also a product of the military supremacy Israel has enjoyed for the past six decades ago.

Obama's near impossible task will be to tame Israel's homicidal instincts, while rescuing the Palestinians from their suicidal instincts. With help from the Arab states and the EU, he must induce them to end the crippling feuds.

What is the answer to the puzzle? The US could offer Israel a formal guarantee of its security. Iran, in turn, might agree to freeze its nuclear programme, if its own freedom from attack were guaranteed - and if the Palestinians were to get their state. Some package deal of this sort may be the only way out of a dangerous impasse. But, for the moment, Israel is in no mood to see reason.

Patrick Seale is a commentator and author of several books on Middle East affairs.