Canada has not yet offered any definitive evidence of Indian complicity in the killing of a Sikh separatist leader, Hardeep Singh Nijjar, in British Columbia in June. The prime minister Justin Trudeau’s recent parliamentary statement noted credible “allegations” of a “potential” Indian link to the assassination. But putting aside the veracity of Canada’s claims, the downturn in Indo-Canadian relations points to signs of a more assertive Indian foreign policy. India has been in the geopolitical spotlight over the past year, as evidenced by it hosting the G20 summit in New Delhi earlier this month. It has surpassed China in population and the UK in GDP. India’s prime minister, Narendra Modi, has received a red-carpet welcome in several capitals, most notably Washington in June. The contrast between China’s struggling economy and forecasts that India will be the world’s fastest-growing major economy this year could not be starker. However, is there a dark side to India playing a more assertive role on the world stage? It has already come under criticism for its position on the war in Ukraine, notwithstanding Modi’s much publicised statement that “today’s era must not be of war”. The spat with Canada points to two additional facets of Indian diplomacy: first, that India could be becoming more prone to taking offence at actions that challenge its sovereignty and status; and second, that it may be more willing to retaliate against such actions. Interestingly, both have parallels with China. This points to both countries’ foreign policies being rooted less in the ideologies of their ruling parties – Hindu nationalism for the BJP and Marxism-Leninism in the case of the Chinese Communist party – and more in the self-perception that they are civilisational states that deserve to be treated as major global powers. Related to this, both countries cling to a need to correct historical injustices. China’s “100 years of humiliation” by the west and Japan is matched by India’s “200 years of humiliation” under British colonial rule. Like China, India has also demonstrated a willingness to employ tools of economic coercion as a form of punishment, notably the prospect of access to its vast market of 1.4 billion people. After the recent tit-for-tat diplomatic expulsions by Canada and India, the likelihood of concluding a free-trade agreement between the countries is negligible for the foreseeable future, despite nine rounds of negotiations (the most recent in July). This is a warning to other countries that have also had tensions over alleged anti-Indian activities on their soil, including the UK: pursuing free-trade negotiations with India might prove difficult. If the allegations of official Indian involvement in the killing are proved to be true, it would also point to the growing brazenness of India’s intelligence services. India has long been active in intelligence and military operations targeting terrorist activities in neighbouring countries, most notably Pakistan, but a state-sponsored assassination in a western country would be a gamechanger. India wants to be seen as a responsible global power. The last thing New Delhi would want is to be put in the same league as Saudi Arabia following the killing of journalist Jamal Khashoggi, or Russia following the Salisbury poisonings. This would put the US in a difficult position. It sees India as a long-term strategic partner and a bulwark against the rise of China. It has downplayed allegations of democratic backsliding and human rights abuses in India. But it cannot ignore an extrajudicial killing in a country that is a key ally. Finally, the downturn in Indo-Canadian relations demonstrates the downside of India’s 18-million strong diaspora population, which is the world’s largest. Members of the diaspora have been touted as a source of strength for India through their role as cheerleaders and virtual ambassadors for the country. This has been reflected in the warm reception that Modi has received from overseas Indian communities in several countries. However, the recent resurgence of Sikh separatist (Khalistani) sentiment in several countries alludes to the diaspora becoming a source of friction between India and host countries where groups are engaged in alleged anti-India activities. The rise of ethnic Indians to prominent positions of power – including Britain’s prime minister Rishi Sunak, the US vice president Kamala Harris, the World Bank head Ajay Banga and 26 CEOs of Indian origin in S&P 500 companies – can build bridges between India and other countries. But it can also fuel frictions. In this context, the fact that Canada is home to the world’s largest Sikh population outside India and the Canadian government includes a coalition partner led by an ethnic Sikh, Jagmeet Singh, has raised questions about the extent to which Trudeau’s government is beholden to groups that sympathise or support Sikh separatist activities in India. Where does this leave India’s international diplomacy? While it may be premature to say that India is engaging in its own form of “wolf warrior” diplomacy, the downturn in Indo-Canadian relations signals the emergence of a more muscular and potentially aggressive Indian foreign policy. Dr Chietigj Bajpaee is senior fellow for south Asia at the thinktank Chatham House