If, in your mind, simply declaring oneself to be something, whether or not the person displays the qualities that are indicative of that thing, is all that is required to be that thing, then I will never be able to reason with you.
I cannot prevent you from believing every non-Christian is a Christian if you desire to do so, but that won't make it true and won't make it reasonable to believe.
So continue calling hateful people Christians if you want, but it won't make them Christians and it won't make people who know better believe they are Christians.