As protests continue in the tiny gulf state of Bahrain, home to the US Fifth Fleet, the Americans and Saudi Arabia are monitoring events there very closely.
The country, with an indigenous Shia-majority population, is ruled by a Sunni royal family, the al-Khalifas.
As events in Egypt gathered pace, human rights activists in Bahrain called for a day of rage on 14 February.
The result on Monday was sporadic protests in Shia villages across the island and attempts to create a "Tahrir Square movement" in central Manama, the capital.
Footage shot by protesters and posted on the internet shows riot police attacking peaceful demonstrators with tear gas and rubber bullets.
Thus far, the government is continuing to respond with harsh tactics. Dozens of protesters have been wounded and two killed.
A 21-year-old man died on Monday after being hit by a rubber bullet. On Tuesday, at a funeral march to protest against his killing, a second man was hit by a shotgun blast and died.
Although protesters have been routinely beaten and tear-gassed by security forces in the past, these deaths are the first of their kind in several years, and are likely to add fuel to a growing anger among ordinary Bahrainis.
The demonstrators, many waving the Bahraini flag, are calling for a new constitution, the release of hundreds of Shia men and boys who have been rounded up since August 2010 and an end to civil rights abuses.
The king went on state television promising to investigate the deaths of the two protesters and offering to set up a committee to discuss change.
"Too little, too late," was the blunt analysis of Nabeel Rajab of the Bahrain Centre for Human Rights.
"Yesterday the people were calling for reform. Today they are saying: 'Change the regime.'"
However, Western analysts caution that an Egyptian-style revolution is unlikely to unfold in Bahrain.
Gala Riani, a senior Middle East analyst at Jane's Defence Weekly says: "Bahrain is not unused to this kind of unrest.
"The authorities will be able to handle it, as they have in the past, if it is sectarian in nature."
But that could be a big if.
Journalist Reem Khalifa, a senior editor with the Bahraini newspaper Al Wasat, says this time the protests are different.
"Young Sunni and Shia are marching together and they are shouting 'neither Sunni nor Shia but Bahraini'. We have not seen this before,'" she says.
She adds that women are much more involved in the protests. One reason is that they are less likely to be manhandled by the security forces.
Even so, Ms Khalifa says she saw one woman who had approached a security line with a Bahraini flag being roughed up.
The security police are largely non-Bahraini. They are Sunni Muslims recruited from Pakistan, Yemen, Syria and Jordan.
Fast-tracked to citizenship and given preferential treatment, they are infuriating protesters.
One protester told me: "Some of [the security police] don't even speak Arabic. They have no respect for the people.
"They have no loyalty to the flag. Their only loyalty is to their paymasters."
Meanwhile, American president Barack Obama may have another headache on his Middle East plate. The Fifth Fleet is seen as a bulwark against the rising threat of Iran.
As in Egypt, US policy has been to ignore the often legitimate grievances of Bahrainis in favour of stability and support for a repressive regime.
But if these protests transcend the sectarian divide and the Bahraini government responds with ever more brutal tactics, Washington will be put in a very difficult place - to support the government will be to deny the democratic aspirations of yet another Arab nation.
And Saudi Arabia is even more nervous - a causeway links the kingdom to Bahrain.
An expert with close ties to the powerful Saudi Interior Minister Prince Nayef told me the Saudi government will intervene if the situation "gets out of hand".
Gala Riani of Jane's Weekly concurs, saying the Saudis would not be loath to lend support - and in a worst-case scenario to intervene directly - should the Bahraini authorities not be able to control the demonstrations.
That would add a nightmarish twist to Barack Obama's growing Middle East dilemma at a time when instability is rapidly outpacing American strategy in the region.
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