Kon, if you check any list of known terrorists, you will find a lot of "Abu"s in leadership positions.
The names they take usually include the name of some (bloodthirsty) early Muslim "saint",and are followed by a distinguishing description: al-Masri (the Egyptian),al-Zarqawi (the Jordanian),etc.
True enough.
They also take Sheik and a few other names too. Its a perfect way to hide in plain site, by using a term of endearment so that wiretaps will seem to reveal they are talking to friends.
Its effective, because its so common in the arab world.
Hope this doesn't cast suspicion on me when I call Aunt Tillie.