From the Wall Street Journal:
The term “Islamofascism” was introduced by the French writer Maxine Rodinson (1915-2004) to describe the Iranian Revolution of 1978. Rodinson was a Marxist, who described as “fascist” any movement of which he disapproved.
No wonder the Neocons love it, being left-leaning faux-conservative big-government Trotskyites.