NEW DELHI: For weeks, India’s young protesters waved signs mocking Prime Minister Narendra Modi and his government and rallied under an unlikely name: the Cockroach Janta Party. They secured a concession few have extracted from Modi during his more than 12 years in power: a cabinet minister’s resignation. Modi has been one of India’s most dominant prime ministers in decades, winning elections while cultivating an image of decisive leadership. His government has rarely been seen to yield to public pressure.

With the Cockroach Movement, India's youth turned rising unemployment and institutional distrust into a political reckoning

The Cockroach Janata Party, founded by young Indians frustrated with a weak labor market, successfully forced the resignation of a top government official—a shocking concession…