Bullshit.
The US wouldn't approve of the attack, it only supplied, the weapons, the means, the technology, and the infrastructure to help carry it out.
This sounds like Israel's going to attack Iran and the US will wag its finger at Israel, pretending it had nothing to do with the decision, so Israel absorbs whatever fallout results, the US government gets of scott free in the eyes of the world, and can continue supporting Israel with impunity even if others' nations choose not to.
I will believe it when the US government demonstrably stands against Israel, politically, economically, and even militarily.
Until then, any strike on behalf of Israel, the blame is multiplied to apply as well to the US govt..
From what I can perceive, All this 'fallout' in relations is song and dance for the idiotic masses to consume. What has changed in terms of what really matters? The business, military, and industrial ties? Absolutely nothing. Words are free, and are thus the least valuable indicator of intention and alignment.
Regardless, on one hand, I think it would be excellent for Iran to be attacked by Israel, especially with a tactical nuke. While of course I wish no lives to be lost or infrastructure destroyed, it would be all that Iran needs to justifiably say, to hell with a peaceful nuke program.
At the same time, from historical precedent I don't think the Israelis, while prone to idiocy, would undertake such actions without carefully planning a strategy and considering all contingencies.
So I am not sure what to expect in this context.