It isn’t that they would do nothing.
Israel will get attacked by somebody out of opportunity regardless.
But attacking Israel won’t hurt Obama.
He hates and despises Israel.
They would have to retaliate in some other way at another location that would hurt zero greatly.
What about an Israeli response? Would that have to be “measured” as well? Tit for tat, no harm done? They can’t throw Chemical rockets at Israel as she will then go nuts.