Prime Minister Justin Trudeau may have taken to Twitter this weekend to defend immigration and diversity, but behind the scenes there’s a formidable ghost bedevilling the machinery of Canadian government – Donald Trump.

The U.S. president’s way of communicating – Tweets, various interview musings and executive order pronouncements – have upended the traditional, time-honoured way of conducting the business of Canada’s relations with its largest trading partner and top ally.

The effect, sources tell The Canadian Press, is historic because the usual way that Canada and most western governments would make foreign policy has been thrown out the window.

The bottom line, they say, is the absence of something very basic – paper.

Trump’s first week in the White House has done away with the usual formula of public administration.

In the pre-Trump world, a foreign government would make an announcement – state its intent to do something – then the paper would follow. That usually meant a written, well-considered policy statement on the way forward, or a piece of legislation that was designed to get the job done.

Canadian bureaucrats would then in turn draft a policy or a response. But their pens are down, sources say, because they have nothing tangible to analyze from the Americans.

The insiders spoke to The Canadian Press on the condition they not be identified because of the sensitivity surrounding the issue.

For the most part, this back-and-forth chaos has meant that Canada’s approach has been to adhere to a very strict and basic strategy – reinforcing the positives of the deeply-integrated Canada-U.S. trading relationship with its intertwined supply chains, said one source.

That explains the almost slavish adherence to the talking points that Trudeau and other cabinet ministers have been using – that 35 U.S. states have Canada as their number one customer, that nine million U.S. jobs depend on trade with Canada.

But on Saturday, Trudeau moved beyond that cautious approach when he used Twitter to react to Trump’s order barring citizens of seven countries, including Syria, from entering the United States.

“To those fleeing persecution, terror (and) war, Canadians will welcome you, regardless of your faith,” read Trudeau’s tweet, followed by one containing a photo of him greeting a young Syrian refugee.

Meanwhile, Trudeau’s officials needed to act swiftly to clarify what Trump’s travel ban would mean for Canadians with dual citizenship. Would they be turned away at the border?

Trudeau’s National Security Adviser Daniel Jean and other officials reached out to their American counterparts, including Trump’s National Security Adviser Michael Flynn, for answers, Trudeau’s spokeswoman Kate Purchase said late Saturday.

“NSA Flynn confirmed that holders of Canadian passports, including dual citizens, will not be affected by the ban,” Purchase said.

That contradicted a statement earlier in the day from the U.S. State Department that said Canadians with dual citizenship from Iran, Iraq, Sudan, Somalia, Syria, Yemen and Libya would be denied entry for the next three months along with citizens from those countries.

The Trump pattern of pronouncements-then-contradictions obscures the connection between what the president said and what gets pursued, sources say.

They cite numerous examples that are sowing confusion, including Thursday’s upheaval over a proposed 20-per-cent border tax on imports from Mexico as a way of making it pay for the U.S. wall Trump wants to build between the two countries.

White House press secretary Sean Spicer later climbed down from the proposal, saying it was just an option for paying for the wall.

Examples of this abounded during the Congressional hearings to vet Trump’s cabinet choices. Trump blasted NATO as obsolete, but his pick for defence secretary, the retired general James Mattis, spoke favourably about the alliance.

On NAFTA, Trump threatened to tear up the deal prior to his election, but just days after his inauguration one of his senior economic advisers offered Canada reassurance.

Stephen Schwarzman, the head of the president’s Strategic and Policy Forum, said there was no need for Canada to be “enormously worried” because it is well regarded and will be in a good position should there be a NAFTA renegotiation.

Canadian officials have signalled a willingness to keep the three-country deal alive; or to pursue a bilateral deal with the U.S. that would exclude Mexico. But their preference is a three-country agreement.

“Definitely that’s still Plan A,” said another source.

“Canadian companies are affected by these supply chains. It becomes pretty cumbersome (to split up NAFTA).”

But the official said everything depends on what Trump does next.

“If we feel going it alone is going to give us a better deal, we have to look after Canadian interests,” said the source.

“But it would be disruptive.”

The internal government confusion is mirrored by the divisions among Canadian analysts over whether Trump can act alone on NAFTA or needs the support of U.S. Congress.

“The President likely has the legal authority to withdraw the U.S. from the NAFTA on his own,” said a recent analysis by the Toronto law firm Bennett Jones.

The firm added that he has “considerable latitude to pull the U.S. from the NAFTA with or without Congressional support.”

But another recent report, from the C.D. Howe Institute concluded, “the ultimate power to withdraw from NAFTA rests with the United States Congress, and not with the president.”