He was a noble soldier who didnt accept the harming of small children, slavery of non-arabs, heavy taxes, and opression of non-muslims. If he was alive today he would kill Abu-Bakr Al-Baghdadi.
There is no muslim world (ummah) except in fantasy world, it's an imaginary concept, as you see in the war between saudi arabia and Yemen, and the dispute between qatar and saudi arabia. They can't unite with themselves, now you want to unite with them against Iran? good luck.
And believe me if allah is strong enough he does not need some 2 legged wahabis to protect his house. Even the birds will carry stones and drop it on anyone who has bad plans for the house of allah.. (reading from your own source)