The article examines the effects of a hypothetical (for now) and possible future nuclear exchange between Iran and Israel.
Israel, due to its small geographic footprint and relatively high population, would suffer catastrophically if even a single nuclear weapon of a size in the neighborhood of as small as 100-kilotons were to explode over Tel Aviv. Many would die in the initial blast but an even greater number would be killed or sickened by radioactive fallout in the aftermath, including the Palestinians residing in the West Bank and many other Arabs in western Jordan.
Iran, on the other hand, would also be devastated, because Israel has much larger warheads as well as a large number of them. Upon detecting a launch against them, Israel would retaliate, most likely decimating every major Iranian city and all of their major military bases. And, they could accomplish this and still have additional warheads in reserve to defend themselves against any other aggressor.
So, obviously, the best option is to keep Iran from getting 'the bomb' in the first place, to which end the article says the Israels are apparently actively planning.