Trump said the tariffs, which will come into effect 15 days after he formally unveiled them Thursday, will not initially apply to Canada and Mexico. But they've stalled over tough US demands, including the administration's insistence that more auto production be shifted to America.
But if the WTO affirms Trump's justification for tariffs, it could encourage other countries to follow the USA example: They could use national security as a pretext for tariffs of their own.
The narrowing of wider tariffs Trump last week announced he would impose preserves an important source of raw materials for OR factories.
European Union officials may challenge Trump's tariffs at the World Trade Organization, but that could be a long, drawn-out process.
"We know we have a problem like, for example, European aluminum dumping", U.S. Rep. Bill Huizenga, R-Zeeland, said.
Last week Gary Cohn resigned from that role after Mr Trump's announcement of tariffs on steel and aluminium imports.
While carrying a message to Washington to push forward a diplomatic breakthrough over North Korea, Chung Eui-yong, South Korea's national security office chief asked US officials to support Seoul's request for a waiver, a presidential spokesman said.
The administration argued that healthy steel and aluminum industries are vital to the national defense.
With hike in tariffs by the United States government, exports of these products to the American market will become expensive and could impact the competitiveness of domestic items.
"The American aluminum and steel industry has been ravaged by aggressive foreign trade practices", Trump declared at a White House ceremony, surrounded by steel and aluminum workers holding white hard hats. As such, the company has been following this issue carefully - and making our voice heard through direct appeals to elected officials - since the U.S. Commerce Department began investigating potential steel and aluminum tariffs a year ago.More news: Tiger Woods within striking distance of first win since 2013
More news: Australia Exempt from US Tariffs
More news: What Does The Data Behind Energy Transfer Partners, LP (NYSE:ETP) Suggest?
And so it wasn't a total surprise to see Trump back down and exempt Canada and Mexico, and then later give one to Australia.
So, I say, let's try it.
Quach dismissed Commerce Secretary Wilbur Ross's recent comments that these tariffs would mean insignificant price increases on cans of Campbell soup and Coca-Cola.
USA factory bosses worry that even within the steel sector itself, manufacturers will be damaged by the tariff. By claiming a link between games and violence - even without evidence to support it - they create the illusion of a threat.
Supporters, however, say it's less about a potential trade war and more about America defending itself in trade just as it would against military aggression.
European nations, though, are already threatening to retaliate with tariffs of their own against such iconic American products as motorcycles, blue jeans and bourbon, among others.
America is the world's largest steel importer, buying about 35 million tons in 2017.
Rather, the worry is that a widening trade war with layers of retaliatory tariffs would depress global trade, which grew 4.2 percent past year, the most since 2011, on the fuel of the global economy.
Treasury Secretary Steve Mnuchin told CNBC in a Friday interview that the president will consider national security, noting that Trump wants to be sure that North Atlantic Treaty Organisation gets more funding from European allies who Trump has previously criticized for not contributing enough. It estimates the 10 percent tariff on the aluminum encasing most of the beer sold in the USA will increase the cost of the beverage by $348 million annually and threaten more than 20,000 jobs in the industry.