I think the flaw in your thinking is that you assume the US is self-sufficient. If that was the case there would be a very small trade deficit and given the sherade about tariffs early last year, this is not the case (IMHO).

As an external person which is actually benefitting from Trump's shanenigans (I am paid in CHF, which are worth more and more as they are considered probably the safest currency there is) I think the current US Administration wants to thread the needle by devaluating the currency enough that debt becomes manageable and exports benefit from a weak USD while remaining the reserve currency.

However, I also believe that for this plan to work you shouldn't alienate your closest allies as they will go trade elsewhere, impose tariffs on you, or trade in Yuans just to spite you. So you are left with a weak currency that is not as important anymore and basically unchanged exports.