Again John I think you are missing the point. You made a statement about Protestants who marry in a civil ceremony, as well as a statement about Protestant Marriages not being Sacramental, because (in part) Martin Luther denied all the Sacraments except for Baptism and the Eucharist (Which he taught a flawed understanding of). However the Church holds a different understanding than what you have posted, that being that Protestants, even though they may not understand or adhere to it, can and do enter into sacramental marriages, if both are baptized. The Church also holds these marriages to be so, until there is proof to the contrary. you then added to the mix, Catholics, either practicing or those who have defected from the Faith. My statements are with regard only to Protestants who have never been Catholics.
The Papal Statements, as well as the Canon Law and CCC are all addressing Catholics, be they practicing Catholics or lapsed Catholics, baptized as infants in a Catholic Ceremony or Adult Converts who later breached Ecclesiastical law. Not Protestants who were baptized and brought up in a Protestant Church.
Yes there are any number of Catholics and Protestants who have entered into invalid mariiages for one reason or another, however the standards that the Church holds for Catholics are different than those imposed on Non-Catholics. The reason is that a Catholic who is (hopefully) better informed and has greater availiblity of the Graces which God provides through His Church is held to a higher standard than someone who has been raised in an enviornment which does not hold the Fullness of the Faith. As Catholics we are not simply given a more extensive and comprehensive access to the Truths of God, but a greater responsibility to live up to and proclaim that Truth.