What's particularly damaging about Trump's approach to tariffs is the uncertainty. The targets don't always make a lot of sense. They're done haphazardly through questionable paths, which means they're subject to legal challenges. They're changed on a whim when Trump decides he needs to make a splash, or when someone says something he doesn't like, or when he wants to blow up a negotiation, or whatever.
It all leads to a situation where business owners and investors can't really be sure what the tariff landscape is 6, 12, 18, 24 months into the future. Will the tariffs survive legal challenges? Who will Trump decide to tariff next? Which tariffs might be increased drastically next week?
That is not an environment that fosters investment and business growth.