Canada's complaint comes as its efforts continue to renegotiate the North American Free Trade Agreement (NAFTA). U.S. Trade Representative Robert Lighthizer hinted at such a prospect when he mentioned in a statement that "Canada's claims are unfounded and could only lower U.S. confidence that Canada is committed to mutually beneficial trade".
The wide-ranging trade dispute, which was filed with the WTO in December and released publicly on Wednesday, is mostly in response to the steep anti-dumping and countervailing duties that the United States has recently slapped on Canada's softwood lumber industry.
Foreign Affairs Minister Chrystia Freeland and Natural Resources Minister Jim Carr called the duties "unjustified" and said the move would hurt Americans.
Canada cited five reasons for the complaint, saying the USA levies penalties beyond what's allowed by the WTO, improperly calculates rates, unfairly declares penalties retroactive, limits evidence from outside parties, and has a tilted voting system in domestic trade panels that, in the case of a 3-3 tie, awards the win to American companies.
It's possible other countries may join this complaint as intervenors, making it a bigger and more embarrassing problem for the USA government.
"It's (saying), 'The entire way in which the USA - you - are conducting your anti-dumping, countervailing procedures, is wrong,"' said Chad Bown, a trade expert at Washington's Peterson Institute.
"These rates tabled lby the USA on uncoated groundwood paper represent the third action that stands to hurt hard working men and women in our mill communities across Canada", says Derek Nighbor, CEO, Forest Products Association of Canada.
They fear that it could ultimately prompt United States President Donald Trump to invoke NAFTA's article 2205, notifying partners of intent to withdraw from the pact after a period of six months.
Last month a US trade panel locked in hefty subsidies on softwood lumber.
The thinly veiled threat gives new rise to concerns for positive progress in the ongoing NAFTA renegotiations ahead of the next round of talks set for January 23 in Montreal.
"Canada is acting against its own workers' and businesses' interests", Lighthizer added.
Canadian newsprint joined softwood lumber as the latest commodity to incur USA import duties, with up to 9 percent levied on various companies.
A massive question is left unanswered: why did Canada file this request at the WTO while the NAFTA renegotiations are underway (and nothing short of arduous)?
"In a normal situation you wouldn't expect this to impact the long-term trading relationship that we've got under NAFTA", he said.
The highly technical 32-page complaint lists 122 trade enforcement actions undertaken by the Trump administration, dealing with imports ranging from Chinese steel to pasta made in Italy. It lists almost 180 cases stretching back 20 years and covering not just the US treatment of Canadian companies, but also its handling of imports from dozens of countries ranging from China to South Africa to Argentina. Global courts have consistently over-ruled US -imposed duties on Canadian lumber.