It was an indirect threat that Russia will eventually attack or otherwise harm the United States.
Trump was not going to allow Zelensky to depict the United States as weak and told him so.
It was offensive. On a conventional level, the United States faces no threat from Russia.
Zelensky is trying to be the tail that wags the dog, and Trump bites.
This delusion by the Ukrainians is everything I feared from them. They think Trump is their enemy, the democrats and leftist Europe their saviors.
It should be a European problem, but Europe can’t do it, and Zelensky knows it. It’s us or nothing.
I heard one of the Fox talking heads say how this contrasts with Zalensky's meeting of European leaders last week. It was a cozy meeting.
I wonder how much those leaders got Zalensky pumped to split the European deep states away from the US. Could be retaliation for tariffs. Could be retaliation for calling NATO weak. Could be many things. But it certainly laid the ground work for Zalensky to get a deal(s) with Europe and cut the US out.
At best it was the indirect threat that you describe.
At worst, one could imagine it was a threat from the globalists. What they did to the good citizens of Ukraine and their country, all to advance their global socialist agenda, they will do to the U.S.
Far fetched?
Look at the country of Ukraine now, with their cities ruined, and a million or more casualties.