You're putting the cart before the horse: the phrase means "Islam is destroyed."
The reference is to the once well-known story of Cato the Elder (also known as Cato the Censor), a Roman senator prior to and during the last Punic War who so strongly believed Carthage was a continuing threat to Rome that he ended every speach in the Senate with the phrase ceterum censeo Carthago esse delendam which means "I am of the opinion that Carthage must be destroyed."
When Scipio Africanus (there were at least two Scipio's known as Africanus, but I digress) conquered Carthage to end the Third Punic War, his dispatch to the Senate announcing his victory contained just three words, the famous Carthago delenda est, in an intentional reference to Cato's constant refrain.
I thank you for the correctio. If the jihadists are not made to desist, the fate of Carthage will be theirs.