It is important for followers of Christ to have a clear understanding of the truth about Islam. It is also important that we do everything we do in a spirit of love.
Islam was invented by a single man who took some teachings from Judaism and Christianity, twisted and contorted them, and invented a new religion based on a false narative about Abraham and Ishmael. The man who created Islam was a warlord, a highway robber (who robbed caravan merchants to fund his wars), a pedophile (who "married" a seven year old child) and murderer. He did not live the life that a prophet of God would live. The teachings of the Qu'ran are there for all to see. Some "moderate" Muslims take a softer stance on the "true" meaning of some uncomfortable verses, but the verses are there and the people who cut the heads off of non-Muslims are not really "extremists", but rather true practitioners of Islam. They are doing the things the Qu'ran teaches them to do as they understand it and as it plainly states the matters.
When Muslims tell me we worship the same God, I say "praise Jesus, I'm glad to hear it, because Jesus Christ is my Lord, my God, and my King..." Then they backpedal. Their understanding of God is the invention of a man, one man. But I don't say things to demean Muslims or "lord" over them or anything else. That would be very unchristian. But I do correct their assertion that I worship the same god they worship, because I don't. But I love them and hate the fact that Satan has so badly deceived them. The lies they are told are very hard for them to recognize as lies. I believe the true spirit of antichrist is in the Muslim religion, so while I am called to love I am not called to compromise with them.