I have spent much of my career as a correspondent in the Middle East, since the Iranian revolution in 1979, reporting crises and wars in which the US and its allies fatally underestimated the religious motivation of their adversaries. This has meant they have come out the loser, or simply failed to win, in conflicts in which the balance of forces appeared to them to be very much in their favour.
It has happened at least four times. It occurred in Lebanon after the Israeli invasion of 1982, when the turning point was the blowing up of the US Marine barracks in Beirut the following year, in which 241 US military personnel were killed. In the eight-year Iran-Iraq war during 1980-88, the west and the Sunni states of the region backed Saddam Hussein, but it ended in a stalemate.