There was no need to guess the timing of the attack on the Lal Shahbaz Qalandar shrine in the town of Sehwan Sharif in Pakistan’s Sindh province. Thursdays are the most important in the week for Sufis and the shrine is particularly crowded with devotees. The Thursday evening attack by an Islamic State bomber claimed more than 72 lives, including that of women and children, and injured more than 150, which makes it one of the deadliest on Pakistani soil in recent years.