MANAMA, Bahrain (AP) ― During one of the nightly clashes with Bahrain’s security forces, a new chant broke out among opposition protesters: “The U.S. is the great Satan.” A few days later, pro-government marchers also waved their fists against Washington.

In a place with almost no common ground left after more than 15 months of Arab Spring-inspired unrest, both sides in the Bahrain meltdown are finding a shared target in the United States.

Their gripes are vastly different ― protesters claiming the U.S. has ignored them, government backers expecting full loyalty from their longtime allies ― but the across-the-board potshots at Washington’s policies point to the deep complexities of U.S. attempts to navigate the crisis in the tiny Gulf kingdom.

Bahrain tugs at just about every critical Gulf issue for Washington. Atop the list: America’s relations with Saudi Arabia as the main patron for the embattled Bahraini monarchy, and the stability of the Bahrain-based headquarters of the Navy’s 5th Fleet, which is one of the Pentagon’s main counterweights to Iranian military influence in the Gulf.

At the same time, the nonstop clashes in Bahrain ― and at least 50 deaths since February 2011 ― have brought critical remarks from Washington about alleged human rights abuses and claims of heavy-handed police tactics.

“But there’s really only so much Washington can say,” said Toby Jones, an expert on Bahraini affairs at Rutgers University. “There’s just too much at stake for U.S. interests.”

This is the slow-drip anger building up among the protesters led by Bahrain’s Shiite majority.

Their demands began last year with calls for a greater say in the country’s affairs, which are tightly run by the ruling Sunni dynasty. The protest cries gradually sharpened to urge for the downfall of the Western-backed king and his inner circle.

In a similar way, the demonstrations once reached out to America for the same moral support given to uprisings in Egypt and elsewhere. In recent weeks, however, the tone toward the U.S. has darkened as protesters feel abandoned by President Barack Obama.

Banners at anti-government rally earlier this month denounced America’s “double standard.”

“Obama supports the killers, not democracy and freedom,” said one message. Another carried a picture of U.S. Secretary of State Hillary Rodham Clinton with the lines: “U.S. interests comes before our freedom.” Some protesters burned handmade Stars and Stripes.

“Obama is the one who had people chanting about change and to fight for what’s right,” said Naba Ali, a 35-year-old woman who works as a sales clerk. “We Bahrainis were inspired by him. And now he has turned his back on us.”

The State Department has issued many statements critical of Bahrain’s crackdowns, such as arrest sweeps and job purges, and use of temporary martial law-style rule last year to convict activists in a special security court. Clinton warned Bahrain it was on the “wrong track” by bringing in Saudi-led forces last year as reinforcements.

Bahrain, in turn, has taken some steps toward reform, including ordering retrials in civilian courts and giving the elected parliament more sway to question and oversee the king’s hand-picked government.

Last week in Geneva, Bahraini envoys told the U.N.’s top human rights body that the country would consider recommendations to release political prisoners, outlaw torture and join the International Criminal Court, a move that could open it to international prosecutions of alleged abuses.

Opposition groups immediately dismissed the pledges as smoke screens. But it highlighted the shifting positions for U.S. policymakers on Bahrain.

Earlier this month, the U.S. said it would resume some military sales to Bahrain after suspending shipments amid the crackdowns. State Department spokeswoman Victoria Nuland described Bahrain’s ability to ride out the unrest as a “a critical component of our commitment to Gulf security.”

Yet she also cited U.S. concerns about “serious unresolved human rights issues” in Bahrain and reports of “excessive use of force” by riot police, which has been accused by rights groups of using birdshot at close range and firing tear gas into homes.

The U.S. decision brought backlash from both sides.

Anti-government protesters chanted against Washington for the planned shipments, even though U.S. official say they do not include crowd control weapons. Hard-line government supporters, meanwhile, blasted the U.S. for its remarks about rights issues.

At one pro-government rally last week, people mocked “Ayatollah Obama” for U.S. comments they claimed as supportive of the Shiite opposition ― which Bahrain authorities say is encouraged by Shiite power Iran.

Banners in Sunni neighborhoods often portray the U.S. as turning its back on Bahrain.

A court Sunday sentenced six people to prison terms of up to 15 years after they were accused of plotting with suspected Iranian agents to topple the kingdom’s ruling system, a defense lawyer said.

The convictions ― which include three activists put on trial in absentia ― reflect mounting claims by Gulf Arab states that Iran has links to the Shiite-led uprising against Bahrain’s Sunni dynasty. Iranian leaders have denounced crackdowns against protesters in Bahrain, but deny any active aid to the demonstrations.

The group was accused of plotting with a “foreign country” ― a clear reference to Iran ― to bring down Bahrain’s Western-allied monarchy. They also were suspected of planning possible attacks on high-profile targets such as the Interior Ministry headquarters and the causeway connecting Bahrain with Saudi Arabia, which is Iran’s main regional rival.

They denied the charges.

The defense lawyer, Mohsin al-Alawi, said the court sentenced six people to 15 years in prison. Three of those were sentenced in absentia, including the son of jailed activist Hassan Mushaima, who is trying to overturn a life sentence imposed last year because of links to the protests. His son, Ali Mushaima, was arrested last month in London after occupying the rooftop of the Bahraini Embassy with other activists.

Al-Alawi says two others received lesser sentences Sunday and were freed because they had already spent six months in detention.