> Seek immediate Security Council action to provide assistance to the signatory if they "should become a victim of an act of aggression or an object of a threat of aggression in which nuclear weapons are used".
Ukraine was the victim of an act of aggression from Russia. Pretty obvious that the US gave its word it would protect them.
> Nevermind the fact that threats of nuclear aggression came much later.
The threats of nuclear aggression were there from the start. What other thing do you think prevents the EU from raining death on the Russians from above.
> Seek immediate Security Council action to provide assistance to the signatory if they "should become a victim of an act of aggression or an object of a threat of aggression in which nuclear weapons are used".
Ukraine was the victim of an act of aggression from Russia. Pretty obvious that the US gave its word it would protect them.