It doesn't matter what Stoltenberg says. The US public is ignorant. Biden only needs to get Austin and Milley to say what he needs to be said. That is all that the Americans will see and hear, their words will be broiadfcast on Fox, CNN, NBC, and that will be the official narrative. Indeed, the narrative has never changed - Ukraine is winning, Russia is losing, Putin is desperate, Putin is crazy.

Voila!

The desperate madman resorts to using chemical weapons on the battlefield.

The desperate madman resorts to using tactical nukes.

In the end, if it is nukes, then it won't matter what the "official line" is - there will be no on e left to hear it anyway.