Iran is the biggest threat, and Putin is helping them directly; he is not hiding that fact. (Obama is also helping them indirectly.) As much trouble as Saudi Arabia is and has been, they don’t have the fanaticism of Iran’s Twelvers, who actually believe they need to start World War III to induce their Mahdi to return.
Helping Islamists in any way no matter where they come from is detrimental to Christians besides.
And Caliphate is a Muslim thing. The Sunnis and Shi’ites differ on who has the right to be the caliph, though.
As for good and evil, their definitions do not change no matter how imperfect the world goes.
You want us to go to war against Iran?