Yes, he has a concern about Israel but his primary fear is what a nuclear war would do to the oil supply. If Iran gets nukes, the Sunni Arab will demand them also. If the promise of US protection is unconvicncing to the Saudis, Pakistan, France, China or even Russia will help them. Nuclear proliferation in the Middle East will spread. It will be only a matter of time until the missiles fly. A nuclear war would shut down oil. That would shut down Western economies including the US. Absolutely impossible to accept that scenario. Bush will hit Iran first.
Iranian parliamentary panel gives conditional nod to nuke deal (Reuters)
from the article: Bush warns nuclear Iran could spur 'World War III'