By KAREEM FAHIM
MANAMA, Bahrain — In a dark alleyway of a low-slung suburb here, two dozen protesters gathered quietly and prepared to march toward a United States naval base. A teenager wrapped his scarf close to his mouth, bracing for tear gas. A man peeked out of his doorway, holding his infant daughter above his head, to show her a ritual of defiance that has become a grinding way of life.
For months, the protests have aimed at the ruling monarchy, but recently they have focused on a new target. To their familiar slogans — demanding freedoms, praising God and cursing the ruling family — the young protesters added a new demand, written on a placard in English, so the Americans might see: “U.S.A. Stop arming the killers.”
Thousands of Bahrainis rose up 16 months ago, demanding political liberties, social equality and an end to corruption. But the Sunni monarchy, seen by the United States and Saudi Arabia as a strategic ally and as a bulwark against Iran, was never left to face the rage on its own.
More than a thousand Saudi troops helped put down the uprising and remain in Bahrain, making it a virtual protectorate. The United States, a sometimes critical but ultimately unshakable friend, has called for political reform but strengthened its support for the government. Last month, the Obama administration resumed arms sales here.
Backed by powerful allies, the government has pursued reform on its own terms. Dialogue between the country’s Shiite majority and the king has stopped. Twenty-one of the most prominent dissidents still languish in prison, and no senior officials have been convicted of crimes, including dozens of killings, that occurred during the crackdown last year. Opposition activists are still regularly detained or interrogated for their words.
On Friday, in what activists called a dangerous escalation, riot police officers forcefully dispersed a rally by Bahrain’s largest opposition party, injuring its leader. Every night, protesters march and clashes erupt, in a violent standoff that often seems a breath away from an explosion.
Some Bahrainis had pinned hopes for reconciliation on a report, issued six months ago, that investigated the events of February and March 2011 and found that the security forces had used indiscriminate force and torture in putting down the uprising. King Hamad bin Isa al-Khalifa promised to heed the report’s findings and punish officials responsible for abuse.
Government officials assert that reforms are bearing fruit, that a new special unit is investigating allegations of abuse, and that thousands of people who lost their jobs because they participated in the revolt or were accused of sympathizing with it have been rehired. Foreign advisers have been hired to overhaul the security services.
The justice minister, Khalid bin Ali al-Khalifa, said the polarization in Bahrain had not “reached a dangerous level yet.”
“It reaches a dangerous level when you don’t have a government in place,” he said, warning also about the increased used of incendiary devices by some protesters. “Many of the people are getting along with each other.”
John F. Timoney, a former Philadelphia and Miami police chief who was hired to help reform a Bahraini police force implicated in torture and killings, said that new curriculums were being taught at the police academy and that police stations were being fitted with cameras to prevent torture during investigations. He also said that the current climate could overwhelm his efforts.
“It’s a heavy lift, changing the culture,” he said. “If there’s no political solution here, it’s all for naught.”
The possibility of a solution seems remote. Opposition groups and human rights activists say that the reforms leave the state’s undemocratic core intact, and that they fail to address central grievances like corruption and the institutionalized discrimination against the Shiite majority.
Nabi Saleh, an island suburb of the capital, graphically illustrates their complaints. A Shiite village in the center is surrounded by seafront homes or compounds that residents say belong to government loyalists, members of the royal family or expatriates. Two slivers of beach are available for the public.
During the day, police officers sit at the entrance to town, tear-gas launchers on their laps, waiting for the inevitable nightly skirmishes with young people in the village.
A few months ago, when one of the village’s few Sunni residents put his house up for sale — fed up with the nightly smell of tear gas — his neighbors begged him to reconsider, and he did.
“This government wants us to separate,” said the man, a business owner who requested anonymity, fearing retribution by the authorities. He added, speaking of the royal family, “When their chairs shake, they take action.”
Men like Ali, 22, a resident of the island, are shaking their chairs. Several months back, during an antigovernment protest, he lost an eye to a concussion grenade fired by the police. After he was fitted with a glass eye, he quickly returned to the streets. He said he had no intention of stopping now.
“Until they fall,” he said.
Opposition activists say the government often casts them as a fifth column, backed by Iran and bent on toppling the Khalifa dynasty, which conquered Bahrain in the 18th century.
At a rally at a Manama mosque last month, a mostly Sunni crowd gathered in support of a proposed union with Saudi Arabia. The monarchy has said such a union would strike a blow to Iranian interference in Bahrain. There is scant evidence of any direct interference, though Iranian officials frequently proclaim their solidarity with the protesters.
People stubbed out cigarettes on a portrait of Ayatollah Ali Khamenei, Iran’s supreme leader. Sheik Abdul Latif Mahmoud, the leader of a Sunni political group, warned darkly of a plot to “redivide” the region.
“Those who created the crisis wanted us to separate from each other on a sectarian basis,” Mr. Mahmoud said.
Bahrain’s mainstream Shiite political opposition has taken a gradualist approach to reform, calling for a constitutional monarchy. “Saying we want to bring the regime down makes Sunnis live in fear,” said Hadi Hasan al-Mosawi of the Wefaq party, the largest Shiite opposition group. “We don’t want to threaten people.”
Opposition activists say Wefaq is losing support from members frustrated with its inability to bring change and independent activists frustrated with its religious focus and limited view of reform. “When a huge number loses patience, what will happen?” Mr. Mosawi asked.
The march on the American naval base, the headquarters of the Fifth Fleet, never reached its destination. When the protesters got to the road leading to the base, riot officers surrounded them and fired tear gas.
It was one of several protests last month that focused on Bahrain’s decades-old alliance with the United States, which includes close military cooperation and a free-trade agreement. Days earlier, the Obama administration announced the resumption of arms sales after a seven-month suspension.
At the start of the uprising last year, a spokeswoman for the United States Navy said that the protests “were not against the United States or the United States military or anything of that nature.”
That has changed. In a Shiite village, protesters burned American flags, and in another, a young man held up a sign reading, “The American administration supports the dictatorship in Bahrain.” Activists frequently liken United States statements — condemning violence by both the government and its opponents — to Russia’s on Syria.
A senior Obama administration official said last month that the weapons sales would not include arms used for crowd control like tear gas. Security challenges required the sale, the official said, adding: “Maintaining our and our partners’ ability to respond to those challenges is an important component of our commitment to gulf security.”
Officials framed the sales as an attempt to support Crown Prince Salman bin Hamad bin Isa al-Khalifa, who was visiting Washington at the time and is seen as representing a reform-minded faction in the government.
Many analysts say it is too late for such a strategy. After the uprising was put down by force in the spring of 2011, they say, hard-liners in the government, backed by the Saudis, became ascendant, eclipsing the reform faction represented by the crown prince.
A young activist with the Bahrain Center for Human Rights who attended the march, Said Yousif al-Muhafdah, said he was unmoved by American assertions that the country was pressuring the Bahraini government. “I don’t want to say Hillary Clinton is lying,” he said. “I want to say this government doesn’t care.”
The American approach faced a critical test this month. Doctors who had been convicted in a military court for their participation in the popular uprising, on charges widely seen as political, appeared before an appeals court. Michael H. Posner, the assistant secretary of state for democracy, human rights and labor, had taken up their case and said he had tried to get the government to dismiss the charges, several of the doctors said.
Mr. Posner was visiting Bahrain when the verdicts were announced: nine of the convictions were upheld. He said the United States was “deeply disappointed.”
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