One nation, American hawks believe, holds the key to subduing and pacifying a Middle East that is giving Washington a severe headache. But it is not Iraq, Iran, or even the increasingly turbulent Palestinian territories. It is a prickly, defiant and repressive state apparently in the grip of its security services: Syria.
Syria is the linchpin in the battle raging for the region. On one side of the conflict stand the United States and its Israeli ally. They bully their opponents, and are swift to resort to threats or brute force. Ranged against them is a motley anti-western alliance - the Tehran/Damascus/south Lebanon axis - with an extension to Hamas, the Islamic resistance movement that, having won the Palestinian elections in January and formed a government, is now under international siege.
Four men represent this alliance: President Mahmoud Ahmad-inejad of Iran, President Bashar al-Assad of Syria, Sayyid Hassan Nasrallah, head of Lebanon's Hezbollah movement, and the Palestinian prime minister, Ismail Haniyeh of Hamas. None of these men is a saint and all have resorted to questionable tactics, but together they form the main resistance to US-Israeli hegemony over the region.
Big issues are at stake: whether the US will remain the unchallenged power in the Middle East, whether Israel can suppress the Palestinians by force and, most importantly, whether small powers can hold their own against a bellicose superpower.
The struggle is particularly ferocious because it is being waged in a context of international anarchy. The flames were fanned by the illegal western invasion of Iraq, which has distorted every political relationship in the Middle East and given a great boost to its most violent and lawless elements.
Amid this chaos, Israeli and American strategists see Syria as the region's weak link. Bring the country to heel, runs their argument, and the whole Tehran/Damascus/Hezbollah/Hamas axis would collapse. An isolated Iran could then be forced to shut down its nuclear programme; Iraqi insurgents would be deprived of jihadi reinforcements; Hezbollah could be disarmed and Lebanon brought into the US-Israeli orbit; and Israel could make short work of Hamas.
In Washington, this thinking produced the Syria Accountability Act 2003, which freezes key assets in the US. President Bush explained that sanctions against Damascus were needed "to deal with the unusual and extraordinary threat to the national security, foreign policy and economy of the United States constituted by the actions of the government of Syria in supporting terrorism, interfering in Lebanon, pursuing weapons of mass destruction and missile programmes, and undermining United States and international efforts with respect to the stabilisation and reconstruction of Iraq". Little wonder that Syria feels it is in America's gunsights.
The challenges that the country faces are vast, and demand a leader of stature. On that matter, the jury is still out. Bashar al-Assad, a mild-mannered, UK-trained ophthalmologist, was placed in power by the nation's barons on the death of Hafez al-Assad in June 2000. But while the father was a master of realpolitik, the son's record has so far been marred by diplomatic blundering, painfully slow domestic reforms and human-rights abuses, which hit a new low in recent weeks with the arbitrary arrest of some three dozen pro-democracy activists.
This raises fundamental questions about Assad's political instincts. Is all-out repression the best strategy for rallying the home front against external enemies? Would the president not be wiser to curb the powers of the dreaded secret police, check the greedy excesses of his immediate entourage, allow the population some genuine freedoms and even co-opt into his government the "patriotic opposition" of human-rights campaigners and civil-rights activists, who are as opposed to accepting the diktat of the US and Israel as he is himself?
President Assad would no doubt argue that if the regional environment were less hostile - if Syria were not caught between the danger of overspill from the war in Iraq on one border and Israel's cruel oppression of the Palestinians on the other - he could afford to become more liberal, as he briefly attempted to do when he took over. Yet his actions present an enigma. Is he, at heart, a reformer manqué, faced with deadly threats to his country and to himself? Is he a reluctant figurehead manipulated by ruthless placemen and relatives? Or has he simply acquired a taste for absolute power on his father's model?
One of the greatest tests that Assad as a leader and Syria as a nation now face is the attempt to strip Damascus of its remaining influence in Lebanon. The challenge has been mounted by the US and France, which have jointly sponsored a United Nations Security Council resolution (number 1680, of 17 May) calling on Syria to establish full diplomatic relations with Lebanon "as a significant step towards asserting Lebanon's sovereignty, territorial integrity and political independence".
Temporarily allied but in reality in competition, France and the US are hoping to step into the vacuum in Lebanon that Syria's ejection would create. Syria has rejected the UN resolution as interference in its internal affairs, signalling that it will not give in without a fight.
This is no mere sideshow to the bigger regional contest. Lebanon is of immense importance to Syria. With Damascus less than 20 kilometres from the Lebanese border and the heart of Syria vulnerable to a thrust up the Beka'a Valley, a basic principle of Syrian policy has for decades been to prevent any hostile power establishing itself in Lebanon, or mounting hostile operations against it from Lebanese soil.
Syria has striven to keep Lebanon away from any relationship with Israel, and firmly within its own sphere of influence. Israel invaded Lebanon not once but twice - in 1978 and again on a larger scale in 1982, when it killed roughly 17,000 Lebanese and Palestinians and besieged and bombarded Beirut. One of its aims was to drive out the Syrians and bring Lebanon under its control, though the attempt failed when Syria managed to abort a US-brokered peace deal between Israel and Lebanon in 1983.
A focal point of the present "struggle for Lebanon" is the investigation into the murder, in February 2005, of Rafiq Hariri, the billionaire former Lebanese prime minister, architect of Lebanon's post-civil-war revival and close personal friend of President Jacques Chirac of France. Hariri was emerging as a potential challenger to Syria's dominance over Lebanon, and Syria has been widely blamed for his killing.
Although it insists it is innocent, the government in Damascus is anxiously awaiting the report of the UN's Belgian investigator Serge Brammertz, due out this month. Chirac, who strongly supported Bashar al-Assad when he first came to power, is now an implacable enemy, and wants the killers brought to justice.
If Brammertz produces hard evidence implicating top Syrian officials, international and domestic pressure on the Assad regime will reach critical levels. The recent wave of arrests of government opponents was a warning to dissidents that the regime is still firmly in charge. But these may well prove to be empty gestures. Should the Brammertz report condemn Assad's inner circle, Syria is likely to face punishing sanctions, which would gravely weaken the Middle East's anti-US and anti-Israeli stance.
Patrick Seale is a Middle East analyst
Syria by numbers
19.04: total population in millions (2005) . . . 74: percentage of population that is Sunni Muslim . . . 3,400: GDP per capita in US dollars (2005) . . . 1918: Arab revolt and establishment of the kingdom of Syria . . . 1920: French rule over Syria begins under League of Nations mandate . . . 1946: independence . . . 800,000: internet users . . . 14: number of regimes throughout history that have occupied Syria (including Hebrews, Persians, Greeks and Romans) . . . 5ft 8ins: average height of a Syrian man (2006) . . . 40,000: troops sent into Lebanon in 1976 . . . 29: years of the Syrian presence in Lebanon that ended in 2005 . . . 17,000: number of people "disappeared" by the Syrian
state in the late 1970s and early 1980s, according to Amnesty International . . . 60: percentage of male population that smokes cigarettes . . . 25: percentage of wives (2005) who reported being beaten . . . 185,180: size of country in square kilometres . . . 58: percentage of Syria covered by the Syrian Desert . . . 420: kilometres of the Euphrates flowing through Syria from Turkey to Iraq . . . 120,000: number of dogs and whores that Yasser Arafat was son to, according to the Syrian defence minister in 1999 . . . 8: number of tourists (in millions) that Syria aims to attract by 2010 . . . 72: average life expectancy . . . 3: percentage of population over 65 . . . 8,000-10,000: date BC from which Damascus, the capital, is thought to have been inhabited . . . 400: years that Syria was under Turkish rule . . . 400,000: number of barrels of oil produced per day (this is the biggest export, though much less than from Syria's neighbours) . . . 92: number of clay tablets on which 3,800-year-old Babylonian beer recipes have been discovered . . . 2007: year of next elections