He shouldn’t but probably can

The Judges Got It Wrong: Trump’s Tariffs Are Legal

19 USC § 2411(b) - Discretionary

“The Trade Representative may take action pursuant to subsection (c) with respect to a foreign country if the Trade Representative determines that an act, policy, or practice of that country is unreasonable or discriminatory and burdens or restricts United States commerce, and action by the United States is appropriate.”