A thought experiment: Let's imagine that God is somehow regional - say He's the God of the Milky Way galaxy. He is Lord over a hundred billion star systems, trillions of planets, uncounted creatures great and small, but that His domain is limited to our particular galaxy. Let's also suppose that the Andromeda galaxy, our neighbor, also has its own god. What if Andromeda's god went on vacation and needed Yahweh to fill in for him while he's gone. So Yahweh agrees and ventures over to Andromeda and presides over that galaxy for awhile, leaving the Milky Way without a god. And while He was gone, He would not listen to or answer prayers, perform miracles, or rule over Heaven and Earth.
How would we know when God left? Would evil suddenly run rampant? Would normally civilized people start worshiping devils and committing crimes and performing vulgar acts? Would future saints not be able to perform the miracles that would promote them eventually to sainthood? Would the birds stop singing? Would the sun stop rising? Would the sky turn dark and stormy? Would the joy of living suddenly be replaced by universal fear and sorrow? Would parents stop loving their children? Would babies stop being born? What indicators would we humans receive that would tell us that Yahweh had once again returned to our own galaxy after being gone for a time?
If the idea of such a regional god seems strange, you may recall how the one true God of the Bible tended to limit His concern to the offspring of Adam and Eve, then Noah, and then of Abraham; mainly the direct descendants of Abraham's grandson, Jacob (AKA Israel).
I want you to ask yourself a very simple question: What does God do? If you say that He does things that would happen naturally anyway, then there is no reason for God to have to do it, is there? It makes more sense to say that God does all the supernatural things; things and events that require divine intervention or a miracle. But the problem there is, no miracles have ever been confirmed as being only possible through supernatural means. Prayers have never been answered conclusively and exclusively by a deity, that couldn't be explained in another way. Mountains have never been moved by faith alone.
If you saw a beautiful sunset and exclaimed "God is good!", how do you know that God made it that way? Even if it is a beautiful sight and a joyous moment for you, it may be the signal of a time of great fear and suffering for others. It may be the last sunset for someone that is dying a tragic and senseless death, leaving behind a loving widow and children. It may be a person that was killed by someone who believed that their god was right and ours was wrong. If you believe that Islam is a false religion; that Allah is a false god, and that Christianity is the one true religion, and that Yahweh (Jehovah, God the Father) is the one true God, remember this: they are the same god. Islam is an Abrahamic religion.