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.
Historical nuclear weapons stockpiles and nuclear tests by country
North Korea joined the nuclear club in 2006 or before. A United States Defense Intelligence Agency report from 1999 projected that both Iran and Iraq would join the nuclear club and have 10-20 nuclear weapons in 2020. However, it is worth pointing out that this report was written before the overthrow of Iraqi dictator Saddam Hussein and before information was released indicating that Iraq had already given up its nuclear weapons program. Even before the U.S. started the nuclear club in 1945, some states (most notably Germany) unsuccessfully attempted to build nuclear weapons.