[Jess Kitting]

. . . should a member state consider its territorial integrity, political independence or security to be under threat.

Hey, the U.S. is a NATO member, and its "territorial integrity" and "political independence" is under threat.

Who's going to come to our assistance?

[AZJeep]

They will, if asked.
US can also trigger Art. 4.
But, I do not think Biden will ask.