As the civil war in Syria enters its third year, there is much discussion of the regimeÂ’s chemical weapons and whether SyriaÂ’s Bashar al-Assad will unleash them against Syrian rebels, or whether a power vacuum after AssadÂ’s fall might make those horrific tools available to the highest bidder. The conversation centers on SyriaÂ’s chemical weaponry, not on something vastly more serious: its nuclear weaponry. It well might have. This is the inside story of why it does not. Relations between the United States and Israel had grown rocky after IsraelÂ’s incursion into Lebanon in 2006, for Secretary of State Condoleezza...