* Trump dismissive of Arab alliances
* Arab leaders struggle to discern policy
* Some admire Trump as strong leader
* Militants may exploit Trump rhetoric
* Gulf Arabs seek U.S. help against Iran
By William Maclean
DUBAI, Nov 9 (Reuters) - The future leader of the Middle East's top foreign ally is, in the words of a Saudi prince, an anti-Muslim "disgrace", openly disdainful of Arab security partnerships, who believes Saudi Arabia would cease to exist for long without the United States.
Donald Trump's presidential election victory means he is the man Washington's Arab allies must deal with after his January inauguration, as they seek U.S. help to end wars from Syria to Mosul, manage humanitarian crises and provide jobs for their populations at a time of low oil prices.
Trump's campaign tirades against Muslim migrants - the target of Prince Alwaleed bin Talal's comments on Twitter - and against Arab allies who don't "pay" for U.S. support suggest the relationship could be delicate.
How far Trump the president will differ from Trump the polarising election candidate is not clear.
Brief, congratulatory messages flowed quickly from Arab allies, including one from Saudi King Salman bin Abdulaziz, who wished Trump success in "achieving security and stability in the Middle East and the wider world".
But underneath the protocol, for many Arab rulers and royals Trump's victory is a source of anxiety. They now face a new America led by Trump who, they fear, could upend a regional order that has prevailed for decades.
Some ordinary Arabs like Trump's no-nonsense style, and praise what they see as his capacity for tough leadership.
"A strong leader ... that is what is needed here in the Middle East and all across the world," said Ali al-Muhannadi, 57, a Qatari owner of an electrical company, filling his car up at a petrol station in Doha on Wednesday.
Muhannadi saw Trump as a useful ally in confronting the jihadist threat, saying he is "very frank and not like a politician. Islamist radicals are bad for the West and for us too".
But privately there are concerns about a lack of clarity in Trump's policies for the world's most combustible region as it struggles to break free from war while trying to safeguard the free flow of its oil exports.
DISAFFECTED ARAB YOUTH
In particular there are worries that Trump's hostile rhetoric towards Muslim migrants will play into the hands of Islamic State and al Qaeda, which are eager to recruit disaffected young Arabs to wage war on the regional governments they despise as stooges of Washington.
Gulf Arab leaders want a U.S. president who understands their concerns after eight years of what they regard as diffidence under President Barack Obama, someone who did not provide the kind of personal contact they value.
In particular they want help to push back against Iran, their main rival. But they fear Trump's public praise for Vladimir Putin will encourage Russia to expand its support for Syrian President Bashar al-Assad, an ally of Iran and an enemy of most Gulf Arab states.
Apart from a commitment to Israel's security, a constant in U.S. foreign policy, and an isolationist tone to his comments, much in Trump's statements about the region remains vague and poorly thought out, diplomats and analysts say.
Opinion is divided about whether Trump's remarks on the campaign trail will be enacted when in office. Among these is his comment that he would consider halting U.S. purchases of Saudi oil unless Riyadh provides troops to fight Islamic State.
Faisal Al Yafai, a commentator at The National newspaper, said many people thought Trump had used his extravagant comments to win votes and once in office he would mellow.
"I am unconvinced. I think he actually believes his rhetoric. It's quite worrying that he doesn't seem to understand how global politics works," he said. "For example you don't go around saying 'if our allies were threatened we wouldn't intervene, why can't they build their own nuclear weapons?'"
"That sort of stuff doesn't help confidence. That collapse of confidence between the U.S. and its allies has a knock-on impact on the economies and in the decisions those countries take on a political level."
Yafai, whose newspaper is based in the United Arab Emirates, noted Iraqis were putting their lives on the line to regain Mosul, Islamic State's main stronghold in the country. "That is not just a war for the region, it is a war for the world," he said.
Others are more sanguine.
A senior Turkish official predicted continued strong relations with the United States and argued that "comments in an election period always have a harder and more hawkish tone than is necessary. But they remain peculiar to the election period."
SAUDIS "READY TO TAKE A RISK"
Prince Sultan bin Khaled al Faisal, a former Saudi special forces officer and now senior fellow at the King Faisal Center for Research and Islamic Studies in Riyadh, said that in U.S. elections "what they say and what they do are two totally different things".
"Foreign policy is not made by one man," he said. "But it's difficult to pinpoint what his policy actually is."
Trump's remarks have been combative, and eye-catching. He has said the United States should be reimbursed by the countries it provides protection for.
Without America, "Saudi Arabia wouldn't exist for very long," Trump told the New York Times in March.
Trump's win drew a cautious welcome in Syria, which has entered its fifth year of war between rebels and Assad's forces.
In Damascus, Syrian member of parliament Sherif Shehada said U.S. policy could shift Assad's way. "We must be optimistic, but cautiously optimistic," Shehada told Reuters by telephone.
Trump's statements on Syria, and his more open-minded stance towards Assad's ally Russia, have fuelled rebel concern about the policy he may adopt on the conflict, in which the Russian air force has been bombing insurgents.
But beyond all that, many officials and observers see another ominous consequence.
Trump's win has not only delighted Western right-wingers but also jihadists who told supporters the election had revealed the true position of the United States towards Muslims.
"The masks have slipped," one supporter said on Islamic State websites. "(Trump's) moronic declarations alone serve us even if his decisions will be under the supervision of the Senate...," wrote another. (Reporting by Hadeel al Sayegh, Noah Browning, Angus McDowall, Nick Tattersall, Aidan Lewis, Sami Aboudi, Tom Finn, Tom Perry, Lisa Barrington, Samia Nakhoul, William Maclean; editing by David Stamp)
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