India denies claim, but not in private talks, say Canadian sources
Neither Trudeau, nor Biden nor any other Western leader has the benefit of their colonial strength and intimidatory capabilities today their forebearers enjoyed where it comes to India or China. Both these countries are now independently strong and economically prosperous driven by a wave of nationalism and patriotism domestically that is funded by the economic and intellectual growth of the past 3 decades. It makes them them forces to be reckoned with.
Trudeau even if he is right about his allegations against the Indian government can do nothing to negatively either impact the image of India or its economic might. There is preccedent that Canada, The US, Britain, Israel, France and Germany have all engaged at some time or the other in self help across borders and in violation of international diplomatic protocols to neutralize threats to their security. This is specially so where their national security is at stake. This self help doctrine was first postulated by Schwartzenberger, the international law professor and author on the subject.
Schwartzenberger first explained the justification of crossing international borders violating the political integrity and sovereignty of an unwilling state to neutralize an enemy where the state hosting the enemy could not or would not deal with the enemy on its soil. His example was Israel's justification for crosssing the Litani river into south Lebanon in 1981 to obliterate the PLO and eject them from Lebanon.
Canada fits Schwartzenberger'ss doctrine perfectly. Pierre Trudeau was first warned by Indira Gandhi of the Khalistani threat in his country It was a warning he blithely, and unwisely ignored. Pierre instead did the exact opposite of what a law abiding leader of a country would do. His government encouraged and funded the growth of the Sikh extrremists movement hosted on Canadian soil and thumbed his nose at Mrs. Gandhi's warnings.
Indira Gandhi was explicit and specific in her warnings. She identified certain terrorists in the Sikh community in Canada and even hinted that Indian intelligence was aware of their sources of funding and political protection and patronage in Canada. Pierre did not like it.
In 1984 Sikhs belonging to the Khalistani separatist movement assassinated Indira Gandhi. Margaret Thatcher referred to these Sikhs as "vile human beings". And she had good reason to fear and loathe them. A couple of years earlier the IRA tried to assasinate her at the Brghton Hotel in England. And a couple of years before that they succeeded in murdering her close friend and minister for Northern Ireland, Airey Neave.
In 1985 the Khalistani Sikhs from Canada placed a bomb on an Air India 182 which was blown up over Ireland killing over 32 innocent people. Canada it seems cannot or will not control its terror problem for domestic political reasons. And to that extent India does have an obligations to protecting its citizens, its integrity as a sovereign nation and its many other interests by taking care of the problem itself.
Attacking foreign embassies and their staff on your soil is also a violation of protocol and international law. Where the law does not work or is selectively applied, people like Trudeau place themselves and their people in harms way.