The thing is, the name Allah is not merely a word for a god, capitalized into God, but is a name for a specific pagan deity; unlike theos, deus, gott, etc. It would be like the Germanic tribes saying, "Can we call the God of the Bible Odin, or Thor?" or the Greeks Zeus, the Romans Jupiter, etc. Our ancestors didn't let the Greeks, Romans, or Germans pick a name of one of the gods from each of their respective pantheons, and let them use that for God; why should we let converts from Islam use the very same pre-Islamic deity name that was preserved by Islam?
I don't see racism at work here; rather, I actually perceive consistency of principle. Not sure where you're coming from, on this. But I believe you're mistaken, sister.
I appreciate the comment and decided to devote an entire post to my response. So about the first comment: The commenter was correct about the specific pagan use for a supreme creator. However, I’d argue that this pagan use of Allah is very different from the pagan use of Zeus or Thor. The apostle Paul didn’t hesitate to make a connection between a specific deity recognized by pagans and the true God (Acts 17:22-31). This Greek deity was “unknown” and Paul immediately made the connection with the concepts of the creator and the supreme deity. It’s very possible that this line of reasoning was used in missionary efforts to people of other nations.
Pagan Semitic peoples who used Elohiym for a creator would have started using it for the Christian God. Pagan Greeks who used Theos for some sort of philosophical conception represented as divine, as Plato did, would have started using it for the Christian God. It would’ve been natural for pagan Semitic peoples who used Allah for a creator to then use it for the Christian God. (This has been mirrored by non-Christians all over the world to use God to convey their supreme deity in English.) Perhaps it wouldn’t be wise for Christians today to appropriate terms from false religions, but I’d be hard pressed to suggest that there was something wrong with the early Christians who did it first.
As for the second comment: Christians have consistently used Allah for two thousand years, following the habit of pagan and Jewish Arabs preceding them. I see no reason to discontinue that traditional use. We Christians didn’t stop using “the Way” once it was appropriated by the Buddhists. We Christians still use Yahweh, Jehovah, and Elohim, which were appropriated by the Mormons. Why should we Christians quit using Allah because it was appropriated by the Muslims?
Now, as for the concern about Christian converts from Islam, I’m not sure what’s appropriate. If they join churches that preserved Allah for linguist or cultural reasons, they are now tied to that pre-Islamic Christian heritage and have a right to anything inherited from their religious predecessors.
Also, since Islam grew out of a reaction to Christianity, and the entire Qu’ran is devoted to criticizing what’s argued to be the Jews’ and Christians’ incorrect and evil views of Allah, in the mind of Muslims everyone’s talking about the same deity, even if a number of Christians disagree. This is something Christians should capitalize on, again following Paul's example on Mars Hill. Ex-Muslim Christians need to use Allah to hit home the idea that Islam does not provide a superior alternative to Christianity.
As for third comment, the part about “racism,” I tried to imply that some sort of “ethnocentricism” was my concern. Many Christians are quick to excuse remnants of Greco, Latin, and Germanic paganism found in American language and culture but criticize any traces of pre-Christian language and culture found elsewhere. I lean towards the position that most of it is harmless, but perhaps that’s better left for another post.