The fact that Hamas continues to fire its silly rockets at "Israel," despite its horrendous attacks on Gaza (ostensibly intended to stop Hamas' attacks) is prima facie evidence that the rationale is false. If it were true, "Israel," a supposedly civilized nation, would have concluded that the "collateral damage" which would probably be required to get Hamas to stop its attacks would be unacceptable, and would have called off the attacks. So, the fact that "Israel" continues its war-crimes spree is all the evidence we need to know that at best, it is not a civilized nation, and most likely, that the purpose of the attacks was always to accomplish what has occurred: massive "collateral damage" and global outrage, except from the US government.
But then, we already know that "Israel" isn't a civilized nation, regardless of what Pat Robertson claims. Even if Hamas stopped attacking, "Israel" would continue to back the Palestinians into a corner and force them to retaliate.