NATO isn't an alliance against Russia. It's a self-defense pact. If any nation is attacked militarily, the others treat it as an attack on themselves and act accordingly (and should invest 2% GDP in military, for example.). It doesn't obligate any nation to participate in an offensive attack against any other nation. And in fact, it doesn't override sovereignty. How they respond to being attacked, in defense, could be nothing. No nation is obligated to participate in any war, defensive or not.
In fact, Russia may even be able to join NATO, since it's in the correct geography. It's also on step one of potential membership, Partnership for Peace. There was a time when some were thinking both in Russia and outside Russia that it too could join NATO. And then there was Putin.
Perhaps you'd have a better case if you said it was an alliance against China, but that too isn't quite accurate either, for different reasons.
Chemistry professors never die, they just fail to react.