Worse, like so many of the BJP’s schemes, the hunt for illegal immigrants is openly anti-Muslim. Some Hindus have been caught in the dragnet, but Mr Shah says they do not need to worry, since the government has drafted a bill to make it easy for Hindu refugees to claim citizenship. Christian, Buddhist, Jain, Parsi and Sikh refugees can too—just not Muslims.
Anything that polarises voters by religion benefits the BJP, especially in nearby West Bengal, where Muslims are over a quarter of the population and the BJP is locked in a political knife-fight with a regional party it accuses of coddling Muslims, the Trinamool Congress. West Bengal is one of the places where Mr Shah has railed against termites. But it is not phantom foreigners, rather the BJP, through its stirring of sectarian tensions, that is gnawing away at the foundations of Indian democracy.