BANGALORE, India — When I met Watareka Vijitha Thero in early 2014 in a suburb of Colombo, the Sri Lankan capital, he had been in hiding for nearly five months. The gentle-voiced monk had spoken out against anti-Muslim fearmongering by a hard-line group called the Buddhist Power Force, known by its Sinhalese initials B.B.S.
Mr. Vijitha’s car was attacked in retaliation, and he narrowly escaped. “What does it mean for Buddhism if those that speak for communal harmony have to hide in fear?” he asked me. “What does it mean for my country that the government lets these lawless thugs have a free run?”
Six months later, Mr. Vijitha was found on a road near Colombo stripped naked and bloody, his hands and legs bound. The B.B.S. denied involvement. When the monk filed a complaint, the police threw him in jail for 12 days on charges of self- inflicted violence — a warning to others who dared to criticize hard-line Buddhists.
Three years ago, the B.B.S and other hard-line groups were fringe elements. Today, they are a powerful force, and their aggressive assertion of Sinhalese Buddhist dominance, in a country that is 70 percent Buddhist, is increasingly mirrored in government-approved revisionist histories of Sri Lanka.
Now, with the country’s president, Mahinda Rajapaksa, facing a challenger in elections on Thursday, hard-line Buddhist groups have mobilized to support him. A wave of populist chauvinism has engulfed the country and sidelined the Tamil and Muslim minorities that make up over a quarter of the population. If it continues unchecked, Sri Lanka will face more instability, ethnic polarization and suppression of dissent.
Extremist Buddhist monks are confounding; they directly contradict a canonically nonviolent religion often perceived as apolitical. Like radical monks in Thailand and Myanmar, Sri Lankan hard-liners reserve special ire for Muslims. The B.B.S. and its counterparts have incited mobs to demolish mosques. A June speech by the B.B.S. chief Galagodaththe Gnanasara triggered anti-Muslim rioting in Sri Lanka’s southern villages; thugs burned homes, four people were killed and at least 80 were injured. But instead of arresting Mr. Gnanasara, the president simply urged “all parties concerned to act in restraint.”
In Sri Lanka, monks have long been involved in efforts to bolster Buddhist primacy. In the 19th century, amid fears that European colonizers and Christian missionaries were diluting Sri Lankan identity, monks led a Buddhist revival, followed by a cultural movement for the dominance of the Sinhalese language over English. These efforts produced a Buddhist nationalism that persisted after independence in 1948 (Buddhism itself is accorded primacy in the Sri Lankan Constitution).
In the last decade, activism by Buddhist monks has grown more overtly political. In 2004, they founded the National Heritage Party, known by the initials J.H.U., and contested elections for the first time; nine monks won parliamentary seats. Though it never espoused violence, the J.H.U. supported the Sri Lanka Freedom Party of Mr. Rajapaksa. As the government intensified its battle against the separatist Tamil Tigers, the monks’ backing gave religious legitimacy to the state’s claim of protecting the island for the Sinhalese Buddhist majority.
The defeat of the Tamil rebels in 2009 ended the country’s nearly 30-year-long civil war. The B.B.S. emerged during this postwar high, deploying a selective reading of Sri Lanka’s origins — excluding the contributions of indigenous and non-Sinhalese communities — to fan fears of an existential threat to Buddhism and justify its acts of violence.
At a rally in 2012, the B.B.S. leader Mr. Gnanasara likened the Sri Lankan military’s victory to the ancient conquest of a Tamil chief by a beloved Sinhalese king. The spectators knew the story and cheered at the comparison. “Tamils have been taught a lesson twice,” he said; so would other minorities if they tried to “challenge Sri Lankan culture.”
In the past two years, hard-line groups have consolidated their political power. The B.B.S. has even used the state-owned cellular network to raise funds. Sri Lanka’s defense secretary, Gotabaya Rajapaksa, the president’s brother, has attended some of their events. The government, meanwhile, denies any links to them.
Rohini Mohan is the author of “The Seasons of Trouble: Life Amid the Ruins of Sri Lanka’s Civil War.