Canadian Prime Minister Justin Trudeau reignited a diplomatic dispute with India on Oct. 13 when he repeated earlier accusations suggesting the Indian government, with the acquiescence of Narendra Modi’s inner circle if not the prime minister himself, orchestrated the assassination of Hardeep Singh Nijjar, a Khalistan activist and Sikh extremist. Canada and India proceeded to expel each other’s ambassadors and senior diplomats. The dispute shows no sign of abating.

Khalistan extremism may not be on Americans’ radar screens now, but that must change. Prior to the 9/11 terrorist attacks, Khalistan activists, those who demand a Sikh state in India’s Punjab, were responsible for the worst airline terrorist incident when a bomb disintegrated Air India Flight 182 over the North Atlantic Ocean, killing 329 people onboard. In 1984, Sikh extremists killed Indian Prime Minister Indira Gandhi. In recent years, Khalistan extremists have twice attacked India’s San Francisco Consulate. Militant Sikh attacks on Hindu temples in the United States are increasingly commonplace.