Nuclear triad
Israel is known to have nuclear-capable aircraft and land-base missiles, with the addition of nuclear-armed submarines this would mean that they now have a full triad of land-, air-, and sea-based nuclear delivery systems some of which would be invulnerable to a first strike by an enemy for the first time in their country's history. No other nation in the Middle East in known to be in possession of nuclear weapons, even though Iran, Iraq, Syria and Libya have started development programs that were never completed.
Treaty on the Non-Proliferation of Nuclear Weapons
South Africa is the only country that developed nuclear weapons by itself and later dismantled them – unlike the former Soviet states Ukraine, Belarus and Kazakhstan, which inherited nuclear weapons from the former USSR and also acceded to the NPT as non-nuclear weapon states.