MUMBAI — In most cities of South Asia, hidden beneath the grime and neglect of extreme poverty, there exists a little Somalia waiting to burst out and infect the body politic. This netherworld, patrolled and nourished by criminals who operate a vast black-market economy, has bred, in Mumbai, a community that has utter contempt for the state, because it knows that its survival depends on corrupting the police. Like underground magma, that underworld has now burst into the streets of Mumbai.

Because the denizens of this netherworld know neither patriotism nor morality, they are easily lured into partnership with terrorists, particularly when they have reason to feel aggrieved. In Mumbai, a large proportion of them are Muslims who were denied space in the formal economy and have developed strong vested interests over the past 50 years.

Details about the Mumbai outrage, where terrorists killed more than 170 people, are still unfolding. But we do know that at least 30 men armed with AK-47 rifles and grenades held India's business and financial center hostage, targeting both Indians and foreigners, particularly Americans and British. It is likely that this operation was propelled from Pakistan through the Lashkar-e-Taiba, a terrorist organization sustained by hatred of secular India and backed by shadowy Pakistani agencies and street support.