SAIMA KHAN wants to die a martyr. Life is transient, she told her father in a telephone call last week, and the real glory is to sacrifice it for Allah. Her statement would be alarming at any age, but Saima is only 10. As she spoke, rifle shots rang out, the acrid smell of tear gas drifted over Islamabad and hundreds of troops surrounded the pro-Taliban Red Mosque, a religious school complex in the heart of Pakistan’s capital where Saima was among hundreds of children being held as virtual hostages in a stand-off between militants and the government. Saima and...