SCOTUS could say he can't with the method he's currently unilaterally doing.
He has a Plan B.
I forgot which provision gives him this but he basically calls it a wartime (not exactly called that) extraordinary financial response
Edit: Here it is:
In the International Emergency Economic Powers Act of 1977 – or IEEPA for short – Congress gave presidents sweeping powers to deal with any “unusual and extraordinary threat with respect to which a national emergency has been declared.” Specifically, when the president declares such an emergency, he then has the power to (among other things) “investigate,” “regulate,” or “prohibit” imports. The word “tariff” or “tax” does not appear in the statute, but the administration argues that the president’s power to “regulate” such trade includes the power to impose tariffs on it.
ber, berrrr, come on man, we're playing together don't get mad.... yah yah we going ATH again, sry that's life, you get 15 mins of winning per 6 months