FOR 65 years, the Nishat cinema stood in Karachi, Pakistan. A giant screen showed blockbuster films from around the world, reflecting Pakistan’s relative openness compared with neighboring Muslim nations. Vast billboards over the door featured handsome movie stars flanked by young women with revealing clothes and long, luxurious hair.

The cinema also symbolized the country’s resilience. Opened in 1947, the year of Pakistan’s independence, the Nishat became a landmark in a lively district of theaters, nightclubs and cafes. An Islamist dictator closed the bars and many theaters after 1977, but the Nishat survived. Crowds attended movies even though boys and girls who sat together risked harassment by religious conservatives.

The show went on until last Friday, when a mob set the Nishat on fire. Although it happened on “Love of the Prophet Day,” a state-sanctioned holiday devoted to protesting an anti-Muslim video made in the United States, the attack was the latest episode in a long-running pattern of self-destruction....