AFTER DAVID BEN-GURION who held the office for over 13 years, Benjamin Netanyahu is Israel’s longest-serving prime minister.Now in his third term, he has led the country for over seven years and has one eye firmly fixed on his legacy.In his latest incarnation, Netanyahu can claim to have steered Israel relatively unscathed through the worst global economic crisis since the Great Depression and kept it sheltered from the tumultuous upheaval in the Middle East. But throughout his time in office he cannot point to any dramatic achievement for which he will be remembered to match Ben-Gurion’s War of Independence and declaration of statehood, Levi Eshkol’s Six Day War, Menachem Begin’s peace with Egypt and bombing of the Osirak nuclear reactor in Iraq, Yitzhak Rabin’s Oslo Accords and peace with Jordan, Ehud Barak’s withdrawal from Lebanon, Ariel Sharon’s suppression of the second intifada and disengagement from Gaza or Ehud Olmert’s deterrent war against Hezbollah and reported demolition of a clandestine Syrian nuclear weapons project near the border with Turkey.Now Netanyahu, the man whose critics deride as a do-nothing prime minister who has wasted most of his time in office, is looking to do something out of the ordinary, to set the seal on his stewardship and secure his place in history along with the great men whose biographies he assiduously devours.One avenue would be a historic peace deal with the Palestinians; another, the scuttling of Iran’s nuclear weapons program.His chief ally on both tracks is his newfound friend in the White House, US President Barack Obama.When Obama visited Israel in late March, the two men struck a “grand bargain.” Netanyahu would show sufficient flexibility on the Palestinian track to enable the US to renew peace talks; Obama would do “whatever it takes,” including military action, to stop Iran going nuclear. It was all win-win for both sides: For the US, both an Israeli-Palestinian accommodation and a defanged Iran serve its wider regional goals; for Israel, success on both tracks would help secure its future as a Jewish and democratic state, free from the threat of nuclear apocalypse.Netanyahu delivered on his end. He freed 26 pre-Oslo Palestinian terrorists, enabling US Secretary of State John Kerry to announce the resumption of peace talks in late July.Since then Israel-US coordination has been extremely close. Obama and Netanyahu frequently talk on the phone, there is an open channel between Martin Dempsey, the Chairman of the US Joint Chiefs of Staff, and IDF Chief of Staff Benny Gantz, and John Allen, a retired American four star general, has been discussing with the IDF Israel’s detailed security needs in the event of a West Bank withdrawal in the context of an Israeli-Palestinian peace deal.With American help, Netanyahu’s grand legacy strategy seemed to be making headway – until late August and Obama’s vacillation over the Syrian government’s heinous use of chemical weapons against its own people. Although the president had warned that the use of chemical weapons would “cross a red line” and trigger an American response, he seemed reluctant to act. His initial dillydallying and subsequent referral of the issue to Congress were widely seen as an attempt to backtrack on his “red line” commitment.Obama’s perceived weakness called into question the credibility of America’s commitments on both the Palestinian and Iranian tracks. After all, if he sought Congressional approval and a broad international coalition for a limited strike against Syria, which had clearly used weapons of mass destruction, what would it take for him to launch a much wider operation against Iran only on the brink of developing nuclear weapons but not using them? IN NETANYAHU’S calculus, an indecisive America with diminished regional prestige would find it more difficult to lead peace talks and worse, if and when the time comes, might not have the stomach for military action against Iran. Netanyahu’s entire legacy strategy seemed under threat. A Palestinian peace deal seemed more remote than before, and on Iran, the prime minister began thinking in earnest once again that Israel might have to act on its own.All this could come to a head early next year. The Americans set a nine-month deadline for peace with the Palestinians due to expire next spring and the Iranians are widely expected to reach nuclear breakout at about the same time.Netanyahu’s legacy aspirations add even more urgency to the mix.In the meantime, the prime minister is playing it cool. He has ordered his ministers not to speak on the Syria crisis or say anything critical of Obama. Housing Minister Uri Ariel, of the right-wing Bayit Yehudi, was given a sharp dressing down by Netanyahu for comparing Obama’s initial failure to act in Syria to the world’s inaction during the Holocaust. Netanyahu, however, reserved the right to make pointed public comments himself.In late August, after a meeting in Jerusalem with French Foreign Minister Laurent Fabius, he intimated how inaction in Syria could impact on Iran’s nuclear ambitions and worse, on the Ayatollahs’ readiness to use them. “Assad’s regime has become a full Iranian client and Syria has become Iran’s testing ground. Now the whole world is watching. Iran is watching and it wants to see what would be the reaction on the use of chemical weapons,” he declared.Netanyahu’s Syria policy is two-pronged: Deterring any possible Syrian, Iranian or Hezbollah retaliation against Israel in the event of an American attack by making it abundantly clear that Israel’s response would be devastating. “If we identify any attempt whatsoever to harm us, we will respond, and we will respond with great force,” he warned.Secondly, behind the scenes, Israeli leaders are quietly arguing the case for an American strike for major strategic reasons.• Failure to act would play into the hands of America’s worst enemies in the region, the Iranian-led Shiite axis – including Assad’s Syria and the Lebanese-based Hezbollah Shiite militia – backed, partly bankrolled and armed by Russia.• Conversely, a successful strike, paving the way for Assad’s ouster, could break the Iran-Hezbollah land connection through Syria, further isolate Iran and perhaps even force the Russians to abandon their last Middle Eastern foothold.• It could also strengthen America’s counter alliance with the moderate Sunni Arab world led by Saudi Arabia, Egypt, Jordan and the oil-rich Gulf States.• For the sake of world order, America must show that there is a heavy price to be paid for using non-conventional weapons.• American credibility and global American leadership are at risk.• America needs to send a clear message to the ayatollahs that it will not tolerate a nuclear Iran and that it will be ready to act to prevent it.The US administration is in full agreement with much of this. Kerry has made similar arguments himself. Indeed, he speaks of a “Munich moment” referring to the 1930s attempts to appease Hitler and implying that America and the international community should act against the Syrian dictator sooner rather than later. Moreover, Obama himself has said he will act whether or not he gets Congressional approval.America, however, faces a real dilemma in Syria. Some top Washington analysts argue that a clear outcome either way in Syria will not serve American interests: an Assad victory would be a victory for the inimical Russian-backed Shiite axis, while a rebel victory could pave the way for alQaeda power-sharing or even domination of Syria. Therefore, these analysts argue, the best scenario for America is for the civil war to grind on. According to this school of thought, if and when Obama strikes, he should do just enough to punish and deter Assad, without tipping the balance of power in the rebels’ favor.But there is another view in Washington: That a fundamental American interest in the Middle East is the cultivation of a wider pro-Western moderate Sunni alliance – that, besides the kings of Saudi Arabia and Jordan, the emirs in the Gulf and General Abdel Fattah Sisi in Egypt, would include General Salim Idris, leader of the rebel Free Syria Army, or someone else in his camp, as head of a new pro-Western government in Damascus. In that case, an American strike should be calibrated to tip the scales against Assad.FOR THEIR part, leaders of the Free Syria Army have told the Americans that if the US takes out key targets in and around Damascus – specifically six air bases and three rocket-launching batteries – the FSA, with an estimated 30,000 men ranged around the city, could relatively quickly take the capital and possibly end the war. They also passed on to the US State Department a detailed plan for handling the leadership vacuum in the event of an Assad regime collapse.But so far Obama’s relations with the FSA have not been clear-cut. Although he has been loath to arm the FSA fighters for fear the weapons could fall into the hands of alQaeda rebels fighting alongside them, there have been reports that American personnel are training FSA fighters in Jordan. Coming down squarely on the side of the FSA could not only alter the course of the civil war in Syria, it could change the balance of power in the region.This is what the Russians fear and why they are so opposed to an American strike.They stand to lose their heavy investment in Assad’s Syria, billions of dollars in weapons sales and other ventures, and, most importantly, their port facilities at Tartous, their only naval base in the Mediterranean, or for that matter, their only naval base outside the Former Soviet Union.For Israel and the waiting international community, there are two big as yet unanswered questions: Given the overarching strategic picture, will Obama have the gumption to act with or without Congress? And if he acts, will he get the scope of the operation right? Too small an attack could be as bad as not acting at all, or worse, it could strengthen Assad and embolden Iran. Too big a strike could trigger a wider regional war. Most importantly, Obama needs to be clear on whether or not he wants to tip the balance in Syria against the Assad regime.If Obama strikes, Israeli leaders are confident Assad will not retaliate against Israel and that the probability of his using chemical weapons tends to zero. He knows that if he attacks Israel, his regime and his life will be on the line. He is unlikely to take the risk.Should Assad nevertheless launch an attack on Israel, Netanyahu would be gifted an opportunity to take major legacy-shaping action – helping to topple the Syrian regime and change the regional balance of power.The chances of that happening though are remote.Netanyahu will more likely have to play a far more sophisticated hand. On both the Palestinian and the Iranian fronts he faces huge Ben-Gurion-scale decisions. He will need to know when to take risks for peace, when to bite the bullet and how far to trust his American partners. In any event, whether he likes it or not, he will find himself embroiled in great region-shaping events, with huge implications for Israel’s future. And the way he copes, the decisions he takes, will determine the legacy he leaves.