The U.S. president has in recent days been making statements to the effect that America should invade Panama, and also Greenland, and use its economic muscle to turn Canada into his country’s 51st state.

On Monday, Stephane Dion, Canada’s ambassador to France, told the Canadian Press that such acts would violate international law.

Jon Allen, senior fellow at the University of Toronto’s Munk School of Global Affairs & Public Policy, agrees with that assessment in no uncertain terms.

“There’s absolutely no question that any effort by Donald Trump to somehow take over the land of another sovereign country is illegal in international law,” he told the National Post. “The effort to take over another country’s territory in part or in whole is one of the fundamental violations of international law.”

As for where to find that law, one need look no further than chapter one of the Charter of the United Nations. The document was signed on June 26, 1945, in San Francisco, and came into force four months later.

It’s like we live in the upside down now

After its preamble — which includes a directive “to practice tolerance and live together in peace with one another as good neighbours” — the Charter states in its opening chapter: “All Members shall refrain in their international relations from the threat or use of force against the territorial integrity or political independence of any state, or in any other manner inconsistent with the Purposes of the United Nations.”

“(Trump) can’t turn this around and say it’s legal,” said Allen. “He may want to do it and he may have American self-interest in doing it, but it’s definitely illegal. And if you can find anybody to tell me it’s legal, I’d be very interested in hearing their argument.”

He added: “These are absolutely ridiculous remarks,” a phrase echoed by Anna Purkey, program director and associate professor of human rights at the University of Waterloo.

“I find it ridiculous,” she said in a separate interview with the National Post. On the issue of Trump’s “51st state” remarks, she noted: “Technically this would also be a threat against the political independence of Canada, essentially saying that Canada shouldn’t be an independent state. I certainly don’t think it’s acting in good faith.”

The prospect of the United States making any kind of military move against Canada or (via Greenland) Denmark also creates a kind of tautology, not just under the Charter of the United Nations but under that of NATO, the North Atlantic Treaty Organization to which all three countries belong.

Article 5 of the 1949 North Atlantic Treaty famously says “an armed attack against one or more (NATO members) in Europe or North America shall be considered an attack against them all and consequently they agree that, if such an armed attack occurs, each of them, in exercise of the right of individual or collective self-defence recognised by Article 51 of the Charter of the United Nations, will assist the Party or Parties so attacked by taking forthwith, individually and in concert with the other Parties, such action as it deems necessary, including the use of armed force, to restore and maintain the security of the North Atlantic area.”

In other words, if the United States attacked a fellow member of NATO, it would be duty-bound to then defend that country against itself.

“The assumption was always that the risk, the threat, would come from outside, and that the countries would band together,” said Purkey. “If one (NATO) country exercises force against another … it would violate their obligations under NATO as well, and to some extent if you’ve violated your obligations, are you effectively a party to that instrument any more?”

Here is where the Vienna Convention on the Law of Treaties comes into play. The 1969 document, which regulates treaties among sovereign states, notes that: “A material breach of a bilateral treaty by one of the parties entitles the other to invoke the breach as a ground for terminating the treaty or suspending its operation in whole or in part.”

So the other members of NATO could decide to tear up the treaty or kick out the offending country. “You’d have the U.S. essentially being out of NATO,” said Purkey. But that would be a drastic move, given the role the United States plays in that organization on a larger scale.

“Would NATO want to do that? Is the U.S. still a reliable party against China or against some other belligerent nation?” she asked. “Would you have wanted to kick the U.S. out of NATO?”

“I have no idea,” she concluded. “It’s like we live in the upside down now.”

Allen noted that, for the time being, Trump’s talk remains just that. “You can say anything you want; in international law, you’re not breaching it until you act. So this might be incitement to an illegality, but just talking about it is not illegal. But it may well hurt American interests and standing in the world.”

But Purkey cautions: “We have to think about these things now, because once these actions are taken, we have to movie quickly. You’re not going to have a lot of time. Once a country takes territory, it’s a lot harder to get them to give it up than to try to prevent them from taking it in the first place.”

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