It's interesting to watch how many news sources reported that President Dementia ordered a halt to all trade with Spain without mentioning that Trump has no power to do that.
While people talk about "U.S. trade with Spain" almost all of that trade is between individuals or businesses in the two countries, not the governments. A company importing olive oil from Spain to be sold in U.S. grocery stores is engaging in "U.S. trade with Spain." Trump can make things more bureaucratically difficult for importers or exporters to that country (whether those difficulties are legal is a different matter, this administration breaks the law constantly) but that would not stop all trade. He could try to impose extra tariffs on Spain, but thanks to last February's Supreme Court decision, it is not clear if those tariffs would ever go into effect.
Trump could try to get Congress to pass sanctions on Spain, but again, that's not something that he could do himself, and Congress is likely to ignore him because, um, why are we doing this?
Kudos to the NYT who at least tried to look into the practical question of what cutting off trade with Spain would mean.