[tacticalogic]

If the objective is to destroy the reactor and prevent it from being used to produce material for nuclear or "dirty" weapons with minimal collateral damage, then you'd want all the damage to be within the containment.

The idea was to use a penetrator to punch a (repairable) hole in the containment dome and rupture the reactor vessel so that everything inside the dome is unsalvagable, including the fissibles.

[agere_contra]

The wiley Israelis may even hit the steel containment with some sort of HESH round that will leave the containment intact, but that will spall the inner surface of the containment off like ragged shrapnel to wreck everything within.

For nested containment they’ll either need a more complex penetrator or one that punches all the way to bedrock (and ground water).