Protestors in Shahbag. (M. Hasan / Flickr)

With daytime temperatures hovering in the low nineties and merciless humidity and air pollution bearing down, it takes a lot these days to draw residents of Dhaka, Bangladesh, out into the streets. And that makes the recent demonstrations in the city's Shahbag neighborhood all the more remarkable. For the past several weeks, thousands have rallied in this nondescript area around a single issue: bringing to justice the collaborators who, in early 1971, helped the Pakistani military put down the Bengali nationalist movement in the country's eastern half. That unrest eventually resulted in the late 1971 civil war that led to Bangladesh's establishment as an independent state.

The collaborators were complicit in the genocide of at least one million East Pakistanis, the demonstrators say, and should be tried in court. Many of them belonged to the Islamist party Jamaat-e-Islami, which dates back to when the British ruled the subcontinent and which has always advocated for an Islamic state. During the 1971 war, it cooperated with the Pakistani military regime because its members deemed that the bonds of Islamic solidarity should trump any Bengali nationalist feeling.

The protesters' timing might seem strange, since the demands for justice and a formal ban on the Jamaat are coming well over four decades after the tragic events. But they are part of a struggle over Bangladesh's identity that has raged for decades. The most recent chapter in the story, the trial and sentencing of several Jamaat leaders, began in 2010. That year, Bangladesh's ruling party, the Awami League, set up an International Crimes Tribunal to address 1970s-era war crimes -- a fulfillment of an earlier campaign promise. The tribunal delivered its first verdict in January. Abul Kalam Azad, one leader, was sentenced to death for murder, rape, and arson. Two others, Delawar Hossain Sayedee and Abdul Quader Mollah, were convicted for mass murder. Sayedee received a death sentence and Mollah got life imprisonment.

The Jamaat and its followers have cried foul. And although the party managed to garner only two seats in the 2008 parliamentary elections, it wields far greater street power among some students, members of the working poor, and political opportunists. Jamaat officials have dismissed the trials as little more than acts of political vengeance and have used the verdicts to stir up ethno-religious hatred. They have waged attacks on secular and Muslim Bangladeshis who expressed support for the convictions, and they were implicated in the killing of Ahmed Rajib Haider, a blogger and a noted social activist. They have also targeted Hindu communities, especially in Noakhali, a southeastern district with a sizable Hindu population. The government condemns the violence but lacks the ability to contain it.

And so goes the latest fight in the war over Bangladeshi national identity. For decades, that national identity has rested on two pillars. First, the country's extraordinary linguistic heritage brings all Bengalis together. Second, since the country's population is nearly 90 percent Muslim, Bangladeshi identity has a religious component. But the country has a sizable Hindu minority, and the perpetual question is whether Bengali solidarity can overcome religious differences to bring the groups together. At times, it has; at other times, it has not.

In the waning days of the British Raj, for example, well-heeled Hindu landowners dominated a Muslim peasantry. It was in those days that religion first became politicized. After the partition of India and the 1947 creation of Pakistan, however, Bengali Muslims felt that their religious identity had been secured. In East Pakistan, they were free, for the moment, to live at ease with the minority Hindu population, whose language and culture they shared.

That fellow feeling became even more important throughout the decade, as it became clear that West Pakistan was attempting to impose the Urdu language on both halves of the country. In 1952, a major student demonstration at Dhaka University against the imposition of Urdu ended with several students being killed by the Pakistani military. This sparked the Bengali language movement, to which both Hindu and Muslim Bengalis belonged.

Over the next two decades, West Pakistan's continued economic and social discrimination against East Pakistan compounded Bengalis' grievances and brought them closer together. In the early 1970s, protestors took to the streets to demand autonomy. That uprising was brutally suppressed in March of 1971 by West Pakistani troops and their collaborators, namely the Jamaat. The massacre left millions dead. In the aftermath, Hindu and Muslim Bengalis began agitating for outright independence from Pakistan. They were supported in their quest by India, which went to war with West Pakistan in December of 1971. After 13 days of fighting, Bangladesh became its own nation. Most Bengalis, regardless of their religious orientation, supported India's intervention and the creation of a new state. The Jamaat, however, stuck firm to West Pakistan's side.

Following independence, Sheikh Mujibur Rahman, Bangladesh's president, banned the party, which faced widespread popular hostility. Many of its leaders fled the country and sought refuge in Pakistan. There, they bided their time until Rahman was assassinated in a military coup in 1975. General Zia-ur-Rahman, who ultimately managed to seize political power, proved sympathetic to the Jamaat and allowed one of its leaders, Ghulam Azam, to return home.

Zia-ur-Rahman was well disposed toward the Jamaat because he wanted to use Islam to legitimize his rule and because he needed the Jamaat's muscle, which had been hardened during the war, to cow potential political opponents maintain control. During this era, the Jamaat regained some respectability, and the nation's common linguistic heritage was systematically played down. Zia-ur-Rahman also introduced changes in Bangladesh's secular constitution to emphasize the role of Islam. To his credit, he was trying to correct some of the errors of the Mujibur Rahman years -- too little progress had been made on postwar reconstruction, public order was a pipe dream, and corruption had permeated all levels of government. Despite his best efforts, however, Zia-ur-Rahman proved unable to amass the legitimacy and popularity he so wanted. Another military coup, in 1981, brought one of Zia's deputies to power. Under Hussain Mohammed Ershad, the turn toward Islam became more pronounced. He formally ended Bangladesh's constitutional commitment to secularism and declared Islam to be the state religion. The plight of the Hindu minority steadily worsened.

For a number of reasons, in the 1990s, Bangladesh made a rocky transition back to democracy. The Jamaat continued to enjoy a limited following because some Bangladeshis were attracted to its parochial ideology. It never won great electoral strength, but in 2008, it became coalition partners with the conservative Bangladesh Nationalist Party, led by Zia-ur-Rahman's widow. It used its position in government to routinely harass religious minorities, attack opponents, and encourage thuggish behavior in its student wing, the Islamic Chattro Shibir. The coalition government fell in 2009 and the more secular Awami League took power.

The Awami League-backed trials of Jamaat leaders have resurrected the horrors of the 1971 uprising and war. But as the demonstrations in Shahbag show, they have also emboldened those who still harbor hopes of a secular and unified Bangladesh. If those protests continue (and continue peacefully), they could be a sign that Bangladeshis reject a xenophobic vision of Islam and are ready for social and political harmony. And in that case, this poverty-afflicted country could, against all odds, become a poster child for religious forbearance everywhere.