Since the end of World War II, the USA and its allies operated on the consensus that trade offers a potent form of inoculation against the outbreak of military hostilities as well as hope for reviving and uplifting economies around the world.
Trudeau said Canada already has "significant barriers" in place to prevent low-priced steel and aluminum from being dumped there, and is prepared to work with Washington to "do even more". Critics called it absurd to claim that Canadian imports threatened USA national security.
The Trump administration earlier approved higher tariffs on Chinese-made washing machines, solar modules and some other goods, prompting Beijing to accuse Washington of disrupting global trade regulation by taking action under US law instead of through the World Trade Organization. But they've stalled over tough USA demands, including the administration's insistence that more auto production be shifted to America.
As is his custom, Trump is forging ahead with a proposal that doesn't really solve the problem at hand, but allows him to pander to his political base.
Needless to say, Canadian officials didn't greet the tariff news warmly.
A third source who had direct knowledge of the administration's thinking said the tariffs, associated with a "Section 301" intellectual property investigation, under the 1974 U.S. Trade Act begun in August a year ago, could come "in the very near future".
Trump tweeted Monday that U.S. "Secretary of Commerce Wilbur Ross will be speaking with representatives of the European Union about eliminating the large Tariffs and Barriers they use against the U.S.A".
Trump has said he will exempt Canada and Mexico from the tariffs and allow other U.S. allies to petition for similar exemptions. Both will be losers and the world trade will suffer as a outcome.
But Mr Turnbull says Australia has a strong anti-dumping regime and it is prepared for steel imports. That war has been raging for decades and we've been losing.
In the last few days, China has warned United States of retaliation. China accounts for 24.8 percent of Korea's total exports, while the US and the European Union make up 12 percent and 9.4 percent, respectively. Of those imports, South Korea, Japan, China and India accounted for 6.6 million tonnes.
"We're going to ensure that Canadian steel is Canadian steel", he said at Dofasco, where he also promised unspecified measures to better protect workers' pensions where companies go under, downsize substantially, or are otherwise bought out.