President Donald Trump is likely to dust off a 1930 trade law largely forgotten for decades to back his new reciprocal U.S. tariffs that will match other countries' higher import taxes, trade and legal experts say.

In my 20 years in international trade law, Trump’s tariff approach is unprecedented in scope, scale, and timing. However, in-house counsel can take practical steps to proactively manage these fast-shifting changes.

Experts say the 1977 International Emergency Economic Powers Act is untested for imposing import tariffs and Trump's action will likely face swift court challenges that could set important precedents.

Canada, Mexico and European countries criticized President Trump’s levies on steel and aluminum with fears that they could ignite a global trade war.