Calling MIRVs cluster bombs is, uh, probably stretching the definition of “cluster bomb” a bit. The problem with the latter is unexploded (but still dangerous)

Calling MIRVs cluster bombs is, uh, probably stretching the definition of “cluster bomb” a bit. The problem with the latter is unexploded (but still dangerous) submunitions that are difficult to find and dispose of once the conflict is over, compare antipersonnel mines. But if you’re hit by a MIRV nuclear strike… well, the issue of post bellum disposal of potential duds is very very far down the list of your problems!