Anywhere on the globe where the US has a significant economic interest the US will act as a partner to preserve said economic interest.

No, it doesn't explicitly say 'this is a security guarantee'. That's where the term 'de facto' comes in: at no point was the Ukraine ever going to be made a member of NATO.

But this wouldn't have been a significant economic interest. The value is uncertain, but no one thinks it's valuable enough that we would commit serious resources to defending it. It's "found money" for the U.S. if Putin decides that he's eaten enough of Ukraine to satisfy his expansion plans - but if he decides he wants more, it's not enough to affect our decision making. So that's why it wouldn't be a "de facto" security guarantee.

Sigh. If Zelensky is willing to grandstand, pout and preen TODAY in the friendliest of environments, what do you think he'd be willing to do in front of the Russians?

Why does it matter what he'd be willing to do in front of the Russians? The Russians are the people who invaded his country without provocation to seize their lands and kill their people. Of course he's going to say - quite publicly - that they are not to be trusted. Just like Reagan was quite willing to tell the Russians in no uncertain terms that their representations are not to be taken at face value.

If the mineral deal was actually important to the U.S., they wouldn't have blown it up just because of a contentious press conference.

BTW, today's episode was very likely how Zelensky treated Biden.

Seems unlikely, since Biden probably didn't treat Zelensky this way.