Sources with knowledge of the Trump administration's thinking say the President's annoyance with Ottawa has actually been building for almost a year: When the Trump administration started NAFTA renegotiations last summer, it expected Canada to gang up on Mexico and help force it to give up auto jobs that had been lured south.
NAFTA is an agreement signed by Canada, Mexico, and the United States, creating a trilateral trade bloc in North America, which came into force on January 1, 1994. "According to English Common Law, even citizens who had emigrated to other nations had no right to forego their British citizenship, and hence their susceptibility for being impressed in times of war", the Foreign Policy Research Institute explained in a chronology of the war.
When Mr. Trudeau announced retaliatory levies on a slew of US goods - from orange juice to pickles - and accused the Trump administration of ignoring "logic and common sense" on trade, Mr. Trump called out the Prime Minister by name in a statement that threatened to tear up the North American free-trade agreement.
Mr. Trump's chief economic adviser, Larry Kudlow, played down the feud at a White House briefing Wednesday. "The lines are open, the negotiations are ongoing".
US stocks, apart from those of steel and aluminum producers, have fallen sharply in response to Trump's recent tariff announcements and other actions against trading partners.
"This approach may work in the short term and in limited cases, but it's not clear it's a winning strategy over time", said Mr Hunter, who was senior director for global economics at the White House's National Security Council under President George W. Bush.
The meeting with Trudeau could be particularly frosty, given Trump's recent sharp criticism of Canada's trade policies and the anger in Ottawa over Washington's decision to justify its new tariffs on national security grounds.
Nevertheless, the War of 1812 remains the last full-scale conflict that pitted Canadian against American, and it remains a point of contention between both countries.More news: Where is Melania Trump? Mystery as public absence extends to 22 days
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Things stand to get worse: While Mr. Trudeau is hoping a meeting with Mr. Trump at the G7 summit in Quebec later this week will calm the waters, the President is mulling further tariffs, including a 25-per-cent levy on Canadian-made cars and trucks.
Canada and Mexico already have retaliated against a range of USA exports that include pork, bourbon and steel, and the European Union has promised to do so as well, raising the specter of a tit-for-tat escalation of protectionist measures.
The White House declined to comment, according to CNN.
In retaliation, all of them have either hit back with their own tariffs on USA goods or threatened to do so, as well as challenging the United States trade measure at the World Trade Organization. When then-prime minister Stephen Harper in 2011 said US approval of the Keystone XL pipeline - which then-president Barack Obama was refusing to do - was a "no-brainer", the White House considered the remark beyond the pale.
"There may be disagreements", Kudlow added. European allies have urged Trump to reconsider. France would also oppose any wording that described the Iran pact as obsolete, the official added.
"We have on various occasions heard the president speak about his interest or his musings about bilateral deals, instead of the trilateral NAFTA that we have", he said.
"I will of course try to speak to the USA president about the current problems that we have overall, in particular on Iran and on trade tariffs", Merkel told the Bundestag lower house of parliament during a question-and-answer session with lawmakers.
"We do seem to be at a little bit of a Rubicon moment in terms of whether or not the United States is going to fundamentally turn its back on this economic order", said Thomas Wright of the Brookings Institution think tank in Washington.