There are many advantages in their being accustomed to the use of arms, and no possible disadvantage.
It's a little like casting out hundreds of fishing lines into the audience. You start getting little bites, then more, then you hook a few, then more. Then you can start reeling them in and that's a loveliest feeling - the whole audience laughing with you.
The Islam of the 18th, 19th and first half of the 20th century was a poor thing. Nobody bothered about it. Islam was that funny sort of pure system of beliefs that depressed people in the Middle East held as their religion.

