Why do people say Jehovah Witnesses are Christians?

Is it because they rewrote the bible, created their own Jesus and called themselves Christians? Jehovah cult is dangerous to Christianity. Jehovah cult aims to destroy Christianity because in their twisted doctrines and mind, we Christians, have corrupted Christianity. How can anyone that is not a Christian like the Jehovah cult, have the audacity to think they're the ones in position to define what is Christianity?