By most estimates, Islam is now the largest non-Christian religion in the United States. And yet some 60 percent of Americans claim never to have met a Muslim. No wonder, then, that so many wild misconceptions about Muslims endure in the United States. Indeed, a third of Americans told Gallup pollsters in July 2006 that they thought America's Muslims are sympathetic to al-Qaeda.

Paul M. Barrett's well wrought and engaging new book, "American Islam," seeks to change perceptions by providing an intimate group portrait of Muslim Americans as they struggle to combat the threats, prejudices and stereotypes that have dogged them since 9/11. Barrett, a longtime Wall Street Journal reporter who's now at BusinessWeek, uses his journalistic skills to insinuate himself into the lives of his subjects -- no easy task in a time of heightened suspicions. The book traces the lives of seven American Muslims, from the wily Dearborn, Mich., publisher and political activist Osama Siblani to the energetic journalist and Islamic feminist Asra Nomani, whose crusade to tear down the wall of separation between men and women in her Morgantown, W.Va., mosque made her a media superstar in the United States and, to her surprise, a scourge in her own community.

Barrett's profiles paint the American Muslim community -- more than 6 million strong and almost infinitely diverse -- as a microcosm of the larger worldwide community of Muslims. Muslims in the United States face the same religious, ethnic and sectarian divides that one finds throughout the Muslim world -- Sunnis and Shiites, Arabs and Iranians, Muslims and Christians. Yet American Muslims have, for the most part, avoided the conflicts of identity and integration that plague so many of their far more marginalized co-religionists in Europe. This partly has to do with economics: While most European Muslims are descended from impoverished immigrant families who flooded into Europe as guest workers at the end of World War II, most Muslims in the United States are, like the protagonists of Barrett's book, either middle-class converts or well-heeled and often highly educated immigrants from a wide array of ethnic backgrounds.

While Barrett maintains a sense of narrative cohesion throughout, the individual profiles are, alas, a bit uneven. His otherwise absorbing chapter on Khaled Abou El Fadl, the renowned theologian and law professor at UCLA, lacks an in-depth discussion of why his theories about Islamic law, or sharia, are so controversial among traditionalist Muslims. And one wishes that Barrett's profile of the charismatic Siraj Wahhaj, the imam of a Brooklyn mosque, had more fully mined the complex history of African-American Islam, its troubling roots in the Nation of Islam and its continuing animosity toward Muslims from the Middle East and South Asia.

Despite these shortcomings, "American Islam" provides a welcome antidote to the widespread Islamophobia that has infected so many Americans over the last five years. Indeed, at a time when global perceptions of the United States are hideously unfavorable, the book makes a compelling argument that the greatest tool in America's arsenal in the "war on terror" may be its own thriving and thoroughly assimilated Muslim community.

Still, it is hard not to be disheartened by Barrett's account of the case of Sami Omar al-Hussayen, a University of Idaho graduate student caught in the wide net thrown upon America's Muslim community after 9/11. Charged in February 2003 with violating the USA Patriot Act for providing "material support" to terrorists by running Arabic-language Web sites that encouraged suicide bombings, Hussayen suffered the same fate as the thousands of other Muslim and Arab Americans who were rounded up and held without due process, often on flimsy immigration charges. Throughout his ordeal, Hussayen insisted that he shunned terrorism and never lost confidence in the American legal system, which he relied upon to find him innocent and allow him to return to his family and his studies. He believed this to be true even after his wife and children were deported to Saudi Arabia in a blatant attempt to force him to "confess" to being a terrorist. He continued to believe it right up to the moment in July 2004 when, having been found innocent of all the terrorism charges, he was nevertheless deported for the most inconsequential visa violations.

While it is dispiriting to read about the bungling overzealousness of a government that has more often treated American Muslims as part of the problem of Islamic extremism than as part of the solution, there is nevertheless something oddly hopeful in Hussayen's unflinching faith that the rights and freedoms for which the United States has for centuries been admired throughout the world would ultimately protect him from harm. Perhaps generations from now, when the war on terror has become little more than a somber footnote in our nation's great history, that may once again be true.

As Muslims say, "Inshallah." God willing.