Over the past week, horrified Indians have protested vigorously on social media and in some cities. The disgust and the fury at the complicity of politicians, and the federal government’s silence, grew into a thunderous chorus demanding that the prime minister speak up and fire the ministers backing the Hindu Ekta Manch.

Belatedly reacting to popular outrage, Mr. Modi finally said: “Incidents being discussed since past two days cannot be part of a civilized society. As a country, as a society, we all are ashamed of it.” He promised justice. His vague statement delicately alluded to another case in the northern state of Uttar Pradesh, where a lawmaker from Mr. Modi’s party is accused of rape. Mr. Modi stayed away from his party’s involvement in both cases.

Yet instead of uniting India in horror, the incident has deepened religious, political and ethical divides. It has also made clear that there is no automatic political cost to crime or falsehood if it furthers the hegemonic political narrative. The politicians involved were sacked only after a huge public outcry. Government ministers, officials, right-leaning media and right-wing supporters have been perfectly sanguine about using the dead child to polarize society with whataboutery, fake news and wild conspiracy theories.

A spokeswoman for Mr. Modi’s party, Meenakshi Lekhi, attacked opposition protests, suggesting that they were selective and opportunistic. “You see their plan,” she said. “First shout ‘minority minority’, then ‘Dalit Dalit’ and now ‘women women’ and then try to somehow fix blame of state issues on the center.” An influential ex-editor tweeted that Muslim Rohingya refugees were to blame for the crime. A B.J.P. youth activist posted a comment, now deleted, on his Facebook page saying that the rape must have been fun. A pornography site reported a surge in searches for videos using the raped and murdered girl’s name.

The sense of national crisis today is because Indians feel a rising urgency to either counter this ethical collapse or to capitalize on it in the run-up to the next election.

Mr. Modi came to power in 2014, and four years into his term, religious and cultural bigotry stands mainstreamed in Indian society.

Many who voted for Mr. Modi’s economic promises are disappointed by his failure to deliver, and impatient with his deliberate silences around sectarian and sexual violence and hate speech by his party colleagues and ministers. The systematic destruction of democratic institutions is hard to ignore.