WHAT THIS MEANS IS IT WILL BE KIND OF A FREE-FOR-ALL.

steel tariffs or import controls in the 1980s and early 2000s. Ross said past attempts failed because the protective barrier had some holes in it.

He suggested the basic problem was Chinese over-production, which creates a global glut, with dumped products finding a way into the U.S. through third countries: “You put a tariff on it coming from one country, they trans-ship it through another one. So it has to be broad. It has to be global in its reach.”

Trudeau said he has spoken with Trump numerous times to press Canada’s case about the potential impact of trade-limiting tariffs and will continue to do so, but it wasn’t immediately clear whether he planned to call again in the coming days.

Numerous press reports cast the president as being in an especially foul mood this week over a variety of developments — ranging from the Russia investigation, to White House infighting between his staff and family members, to the departure of close allies.

An NBC report quoted a U.S. official describing the president as “unglued.”

Conversations between officials are happening on other fronts.

Foreign Affairs Minister Chrystia Freeland, Finance Minister Bill Morneau, Trudeau aide Gerald Butts, Transport Minister Marc Garneau, and Natural Resources Minister Jim Carr have reached out to American officials or the business community in recent days.

Garneau even chatted with Ross in Florida during a satellite launch, which they were both attending as news of the tariffs broke Thursday. He said Ross was non-committal.

This dispute has rattled trade wonks more than most.

One veteran analyst says tariffs are bad economics — but that’s not what scares him most. Gary Hufbauer of Washington’s Peterson Institute said the tariffs could create 5,000 jobs in the U.S. steel industry, but kill 10,000 elsewhere in the economy.

Hufbauer said he fears the risk of a cascading series of reprisals that threaten the stability of the post-Second World War trading system, where any country can use any national-security excuse to impose tariffs.

“It’s bad (for the economy). But on the global stability side it’s much worse,” Hufbauer said. “What this means is it will be kind of a free-for-all.”

One organization born from the postwar order issued a rare public warning Friday: the World Trade Organization expressed concern about the prospect of escalation, and a damaging global trade war.

Hufbauer did offer one cheerful prediction.

He said he believes that, by necessity, Canada and Mexico will get exempted from tariffs. He suspects they will be forced to respect a quota, ensuring exports to the U.S. remain at current levels, so that the northern and southern neighbours don’t become conduits for shipping excess supply into the U.S.

“If I’m wrong,” Hufbauer added, “this will just poison the NAFTA talks.”