Does the term non-Christians include --- Catholics ?
Being the OP, I try to answer your questions.
The term non Christian or Catholic is nothing more than a label that's available if one wants it.
Since both are to be understood in a religious context the labels are not important, it's about do we want to belong to a club or have a personal relationship with a Creator, so one must put all things into a order as not to be confused and understand the meanings and disregard the labels as labels are empty boxes with no value in them.