How a killing in Canada has caused a geopolitical crisis that is sending shock waves through India, the United States and beyond. Read more:On Monday, Canadian Prime Minister Justin Trudeau alleged in a speech to Parliament that agents of the Indian government killed a Canadian citizen, Hardeep Singh Nijjar, on Canadian soil. Nijjar, a Sikh separatist leader, was killed in June in British Columbia..Trudeau’s announcement led to the Canadian government expelling an Indian diplomat. India denied the allegations and expelled a Canadian diplomat in return. Canada has called upon its allies to publicly condemn the killing, just as countries including the United States are hoping to bolster their relationship with India in hopes of fending off China. The Post’s South Asia correspondent Karishma Mehrotra walks us through how we got to this geopolitical crisis and what it means for India’s global relationships.