Amnesty quickly sided with Mr. Begg and suspended Ms. Sahgal before ousting her. Is “jihad in self-defense . . . antithetical to human rights?” asked Amnesty’s acting secretary general in a letter to activists. “Our answer is no.”

The Sahgal affair, and others like it, impelled Karima Bennoune to write “Your Fatwa Does Not Apply Here.” The author, an Algerian-born law professor and former Amnesty staffer, says that she was alarmed by how “the Western (and global) Left often refuses to recognize the reality” of Islamist violence “and the actual danger posed by its ideology.” She was enraged by the blindness of the human-rights establishment because “I am in their camp.”

Her gut-wrenching book, the result of two years of traveling and reporting, is meant as a wake-up call to her comrades on the left. Ms. Bennoune profiles dozens of poets, journalists, artists and average Muslims who resist Islamism, often at great personal cost and with scant support from Western liberals. From the American Midwest to Kabul, from Mali to Fiji, Muslims—Shia and Sunni, devout and irreligious alike—are being squeezed by theocrats and extremists.

In Lahore, Pakistan, Ms. Bennoune meets a theater director whose annual World Performing Arts festival was the target of an Islamist bombing in 2008. The festival stars and caters to children, and had the perpetrator, a 12-year-old peddler-turned-terrorist, been more adept at using IEDs, the attack could have claimed thousands of young lives. Yet despite the bombing and subsequent threats, the director, his actors and their parents still turn up. They need art “like oxygen,” as Ms. Bennoune says.

In Minnesota, she meets Said Salah Ahmed, a refugee educator and playwright, who “no longer feels comfortable writing a play to be produced for his own Somali community in Minneapolis.” Minnesota is home to the largest Somali community in the U.S., which has become a fertile recruiting ground for al Shabaab, the Somali branch of al Qaeda. Mr. Ahmed recalls being prevented from attending a Somali concert in Minneapolis by a censorious crowd “surrounding the theatre saying, ‘Don’t enter. You are paying your money with sin.’ ”

A special area of interest is Ms. Bennoune’s native Algeria. Her father was a prominent intellectual and opponent of the ruling military regime in Algiers. Yet he also dared to teach Darwin at the height of the country’s Islamist insurgency in the 1990s. He survived death threats from armed Islamists, but others weren’t so lucky. “Some victims were picked up at false checkpoints,” she writes. “Others failed to respect the ‘orders’ of the armed groups or went to school or worked as professionals—all considered punishable ‘crimes’ by the fundamentalists.”

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