June 18 (UPI) -- Unlike its Lebanon intervention in 1982 and the current conflict in Gaza, the principal wars Israel fought were very short and one sided: 1956, 1967 and 1973.

How long the current battle with Iran lasts and how it ends are unlikely to be decided after a few days of fighting and aerial combat. But among the "unknown unknowns" former U.S. Secretary of Defense Donald Rumsfeld was fond of assessing, here is one to consider.

Is this war possibly the last crusade against state-sponsored religious violence and radical Islam? Crusade is an inflammatory word. But with the destruction of Hezbollah, the defeat of Hamas and the overthrow of the Assad rule in Syria, Iran was increasingly vulnerable.

That also means that its form of radical Islam has been weakened. That does not mean ISIS, al Qaeda and other radical groups are less threatening. They are, however, if Iran is defeated or neutered without broader cover and thus greatly weakened.

The Sunni Gulf Arabs have agreed at least to a de facto detente with Israel. The other large Muslim states, namely India and Pakistan, are disinterested in this battle. And Egypt signed a peace deal with Israel more than 50 years ago.