The president made no mention of struggles for greater rights in neighboring Saudi Arabia, another close ally.

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Suddenly, Shia populations in eastern Saudi Arabia, Syria, Lebanon, Iraq, and Bahrain could demand greater recognition, an end to discrimination, maybe even some form of autonomy.

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All but a couple of Saudi Arabia's 11 close neighbours facing a degree of unrest, and those two, Qatar and the United Arab Emirates, have tiny native populations, proportionally even greater hoards of cash, and traditions of openness and tolerance that contrast starkly with Saudi Arabia.

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Such concerns may produce a greater degree of mutuality of interest with the United States as relates to countering terrorist operations within Saudi Arabia.

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While the UK was not "sitting on the sidelines", there were more constraints over Syria than in Libya - there was no authority for military intervention from the UN, the effect on surrounding countries such as the Lebanon, Israel and Saudi Arabia had to be taken into account and military intervention would have to be "on a vastly greater scale" than in Libya.

BBC: Hague: 'Deeply frustrating' situation in Syria