“Only strategic bomber…penetrate airspace…S-400s…HQ-9s”
Against a first rate military power? Theoretically. Terrain dependent. If the enemy lacks good AWACs coverage. Leaves gaps in it’s IADS, and enemy territory is large enough to dilute it’s coverage. And if the pilots are lucky. Then maybe. It’s a crap shoot.
Also, B-2 is a strategic bomber, and it has at least as good as chance at penetrating an IADS ??? as the B-1B where the terrain is not perfect for masking the B-1Bs. Chinese and Russian IADS are not what the Soviet network was.