ISIS members are baffled as to why their brand of medieval religious oppression and global terrorism did not succeed, they have revealed.

Surviving jihadis are wondering if publicly announcing they would kill anyone who did not submit to a horrendous way of life may have limited the movement’s appeal.

ISIS fighter Ahmed Al-Jazrawi said: “Looking back, I think antagonising absolutely everyone in the world probably wasn’t the smartest move.

“The strong possibility of being killed by a US drone or dozens of other enemies definitely created recruitment challenges that don’t exist for, say, Asda.

“We also failed to sell the idea of living in a backward religious dictatorship. I think that’s a bit of a turn-off for people who don’t like being flogged all the time.”

Fellow jihadi Abdullah Mohammed said: “With hindsight, setting up a global Islamic state was overambitious. We should have started somewhere smaller, like Wales.

“I’d assumed we’d trigger the apocalypse and God would sort everything out, but it turns out ancient prophecies aren’t very reliable.”