What would happen if Israel violated an American red light may hinge on the results of an attack on Iran. If the attack resembles the 2007 bombing of the Syrian nuclear reactor, which was destroyed, eliciting no Syrian response, the strategic alliance between Jerusalem and Washington may hold firm at some levels, and even recover over time.

However, if the mission is not a clear-cut success, if Iran’s nuclear march is not halted or significantly set back, if the Iranian people unite behind their increasingly illegitimate regime, if Iran strikes out and severely harms American troops in the region, if America’s Gulf allies are overrun and if world oil prices shoot up and stay up, then there is a strong possibility Washington could decide Israel is a country that is not entitled to American support.

Israel could lose its best friend in the world. America could withdraw its support for Israel in the Security Council, where Israel will face severe diplomatic fallout, and even sanctions. America could halt military assistance to Israel. Then we would truly be all alone in the world…

At the end of the day, it may all come down to how clear and explicit the American red light to Israel is. If President Obama looks Prime Minister Netanyahu in the eyes and says, “Absolutely not,” then it will be extremely unlikely Israel will attack Iran. But in politics and diplomacy, there are many different ways of saying no, many different ways of interpreting a “no,” many different shades of red. Sometimes things are not so cut-and-dry, red is not always black and white.