Yes, it's never a good idea to underestimate the intelligence or agency of the enemy.
But in this case: what is the game plan? What are they trying to achieve? Is it simply chaos, so that they can rule in perpetuity?
My interpretation: "No one really knows what will happen but it could work to bring some production back to our country, let's give it a try, if it doesn't we try something else."
One thing they do is allow him to raise taxes on the middle class and poor, who will be paying those tarrifs, while lowering the taxes for the rich. Everyone's talking about some 3D chess when "more money for the rich" has always been the only consistent Republican policy.