I’ve read the book, and its thesis has relevance to the current struggle between jihadist Islam and the West. The thesis is that Jesus was a zealot (small “z” to distinguish him from Josephus’s 4th philosophy) who advocated violent overthrow of political Rome and religious Temple Authorities; he was crucified for sedition.
This thesis is a reply to Pope Benedict XVI’s Regensberg Address, who argued that violence in the name of religion is irrational. Alsan, in essence, shouts back: “Hey, you Christians, how dare you criticize Islam for its origin and tradition of Violence, when your Messiah did the same?”
This is what Muslims will never understand: that a revolution of the spirit is something utterly and completely different than forced conversion by the sword.
That Muslims can’t see the difference shows one of the big problems with Islam.