President Barack Obama and Israeli Prime Minister Benjamin Netanyahu presented a united front Monday at the White House, stressing their shared commitment to preventing Iran from obtaining a nuclear arsenal. They also emphasized their mutual desire to achieve that goal without the use of military force -- if possible.

Therein lies the rub: Define "if possible."

President Obama told reporters at the White House: "Both the prime minister and I prefer to solve this diplomatically."

Prime Minister Netanyahu said: "Israel and America stand together." But he added that Israel must remain "the master of its fate."

The two daunting options that face our two nations as they "stand together":

1) Israel and/or the U.S. can launch air strikes aimed at derailing Iran's accelerating advance toward nuclear weaponry.

2) Israel can agree to defer that action while the U.S. pushes forward on the diplomatic and economic-sanctions fronts.

Option No. 1 would inflict near-certain collateral damage that includes not just the killing of Iranian civilians but the inflaming of Mideast tensions -- and a severe disruption of global oil supplies. Option No. 2 would risk Iran reaching its nuclear-arsenal goal, giving it immense leverage while placing Israel at an unprecedented risk of annihilation.

Gen. Martin Dempsey, chairman of the U.S. Joint Chiefs of Staff, told CNN on Feb. 19 that military action against Iran wasn't warranted because its nuclear ambitions were "unclear."

The general also called the Iranian government "a rational actor" -- a strange description of the major state sponsor of global terrorism. And future Iranian regimes might be even more dangerous than the current one.

So yes, President Obama offered timely reassurrance Monday in saying the U.S. "will always have Israel's back." Yet that doesn't change Israel's core resolve to never again be dependent on other nations for defense.

Sen. Lindsey Graham, R-S.C., underlined that principle on "Fox News Sunday": "The Israeli government and people will not lose control of their own destiny, period."

The armed services committee member offered this blunt assessment of the diplomacy/sanctions option: "We've been talking to Iran for three years. They keep enriching. We've been sanctioning Iran seriously, I think in an effective way for about the last six months, they keep enriching."

So stay hopeful for a peaceful way out of this mess. But don't let Monday's united front foster the illusion that the U.S. has veto power over Israel's options. If Israelis believe their very existence is in direct peril, their sense of self-defense reality will trump any notions of international unity.

And considering the Israelis' history, who could blame them?