Lebanon's Hezbollah militant group is preparing for a possible war with Israel to relieve perceived Western pressure to topple Syrian President Bashar Assad, its guardian ally, sources close to the movement say.
The radical Shi'ite group, which has a powerful militia armed by Damascus and Iran, is watching the unrest in neighboring Syria with alarm and is determined to prevent the West from exploiting popular protests to bring down Assad.
Hezbollah supported pro-democracy movements that toppled Western-backed leaders in Tunisia and Egypt, but officials say it will not stand idly by as international pressure mounts on Assad to yield to protesters.
It is committed to do whatever it takes politically to help deflect what it sees as a foreign campaign against Damascus, but it is also readying for a possible war with Israel if Assad is weakened.
"Hezbollah will never intervene in Syria. This is an internal issue for President Bashar to tackle. But when it sees the West gearing up to bring him down, it will not just watch," a Lebanese official close to the group's thinking told Reuters.
"This is a battle for existence for the group and it is time to return the favor (of Syria's support). It will do that by fending off some of the international pressure," he added.
The militant group, established nearly 30 years ago to confront Israel's occupation of south Lebanon, fought an inconclusive 34-day war with Israel in 2006.
Hezbollah and Syria have both denied that the group has sent fighters to support a military crackdown on the wave of protests against Assad's rule.
Hezbollah believes the West is working to reshape the Middle East by replacing Assad with a ruler friendly to Israel and hostile to itself.
"The region now is at war, a war between what is good and what is backed by Washington... Syria is the good," said a Lebanon-based Arab official close to Syria.
He said the United States, which lost an ally when Egyptian President Hosni Mubarak was overthrown in February, "wants to shift the crisis" by supporting protests against its adversary.
"For us this will be confronted in the best possible way," he said, speaking on condition of anonymity.
Analysts rule out the possibility of a full-scale regional war involving Syria, Iran and Lebanon on one side against Israel backed by the U.S. A war pitting Hezbollah against Israel was more likely, they said.
"There might be limited wars here or there but nobody has the interest (in a regional war)," said Lebanese analyst Oussama Safa. "The region is of course heading towards radical change... How it will be arranged and where it will lead is not clear."
Hezbollah inflicted serious damage and casualties by firing missiles deep into Israel during the 2006 conflict, and was able to sustain weeks of rocket attacks despite a major Israeli military incursion into Lebanon.
Western intelligence sources say the movement's arsenal has been more than replenished since the fighting ended, with European-led UN peacekeepers in southern Lebanon powerless to prevent supplies entering mostly from Syria.
Syria, which borders Israel, Lebanon, Iraq, Turkey and Jordan, has regional influence because of its alliance with Iran and its continued role in Lebanon, despite ending a 29-year military presence there in 2005. It also has an influence in Iraq.
"If the situation in Syria collapses it will have repercussions that will go beyond Syria," the Arab official said. "None of Syria's allies would accept the fall of Syria even if it led to turning the table upside down -- war (with Israel) could be one of the options."
The Lebanese official said: "All options are open including opening the fronts in Golan (Heights) and in south Lebanon."
Palestinian protests last month on the Lebanese and Syrian frontlines with Israel were "a message that Syria will not be left alone facing an Israeli-American campaign," he said.
Israel and Syria are technically at war, but their frontier had been calm since the war in 1973, when Israel repelled a Syrian assault to recapture the Israeli-occupied Golan Heights.
For Syria's allies in Lebanon, the first step to support Damascus has already been taken. After months of delay, Prime Minister Najib Mikati formed a new Lebanese government last week dominated by pro-Syrian parties, including Hezbollah.
That followed five months of political vacuum after Hezbollah and its allies toppled Western-backed Saad Hariri's coalition in a dispute over a UN-backed tribunal investigating the killing in 2005 of statesman Rafik Hariri, Saad's father.
The tribunal is expected to accuse members of the Shi'ite group in the killing, and some Lebanese had believed that the delay in forming a government was deliberate, to avoid the crisis a new government might face when indictments are issued.
"Our people thought at first the vacuum would be in our interest but after the events in Syria we have noticed that the vacuum is harmful," said the Lebanese official.
The still confidential indictment was amended last month after the prosecutor said "new evidence emerged" but Syria and its allies suspect it will now target Syrian officials. Both Syria and Hezbollah deny any role in killing Hariri.
The official said the new government might halt the state's cooperation with and contribution to funding the court, as well as withdrawing Lebanese judges from the tribunal.
"The government in its new form will not allow Lebanon to be used against Syria, or those who are promoting the American agenda on the expense of Syria," he said.
Tension in Lebanon increased in the first weeks of the uprising against Assad when Syria accused Hariri supporters of funding and arming protesters, a charge they denied.
"As Syria stood by Lebanon's side during the July war in 2006 (between Hezbollah and Israel), Lebanon will be on its side to face this war that is no less dangerous," the official said.
So far, Syria's allies believe that Assad has things under control and that the unrest, in which rights groups say 1,300 people have been killed, has not posed a threat on his rule.
While Hezbollah's fate is not linked exclusively to Assad's future, his departure would make life more difficult for the group, which depends on Syria's borders for arms supply.
"Syria is like the lung for Hezbollah...it is its backup front where it gets its weapon and other stuff," said another Lebanese official who declined to be named.
Formed under the guidance of Iran's religious establishment, Hezbollah had a thorny start with late President Hafez Assad, but later emerged as a powerful Syrian ally. Relations improved further after Bashar succeeded his father in 2000.
"Hezbollah is extremely tense and they are concerned about the developments in Syria," said Hilal Khashan, a political analyst at the American University in Beirut.
"The storm is building up now and after it everything will change...In all cases, no matter what happens in Syria, developments there will not be in favor for Hezbollah."
While he dismissed the possibility of a regional war, Augustus Richard Norton, author of a book on Hezbollah, said an Israeli Lebanese war may be possible, adding he believed Israel was likely to strike first.
"It is not too challenging to imagine a scenario for a war between Israel and Lebanon to erupt, especially given the Obama administration's diffident and permissive approach to Israel.
"It is far more likely that Israel will pursue a war with the goal of crippling Hezbollah and punishing Lebanon than that a war will be intentionally provoked by Hezbollah," he said.
In the meantime Hezbollah, which has praised other Arab uprisings and enjoys strong support among ordinary Arabs over its confrontations with Israel, has seen its image tarnished because of its support for Assad.
"The events in Syria have not impacted Hezbollah in a significant strategic sense, but have certainly put the party in an uncomfortable position," said Elias Muhanna, a Middle East scholar at Harvard.
"The fact that (Hezbollah leader Hassan) Nasrallah has supported the regime's war against the opposition in Syria while attacking similar regime actions in Tunisia, Libya, Egypt, Bahrain, and Yemen has been pointed out by many as a blatant double standard."
Hezbollah argues there is no contradiction in its position, saying Assad has popular support and is committed to reform.
"When the regime is against Israel and is committed to reforms then Hezbollah decision is to be by the side of the people and the leadership through urging them for dialogue and partnership," the Lebanese official said.
"That is why the group is in harmony with itself when it comes to Syria. It has its standards clear," he added.
"For the resistance and Iran, the partnership with Syria is a principal and crucial issue, there is no compromise. Each time Syria is targeted there will be a response."
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