Indeed He was, but by that logic Mary's parents were grandparents of God, and which type of attribution can be ascribed to all her ancestors back to Adam.
I see the counsel of Ratzinger regarding title 'Co-redemptrix' is applicable here, as he at least recognized that the title 'Co-redemptrix,'
departs to too great an extent from the language of Scripture and of the Fathers and therefore gives rise to misunderstandings... For, Everything comes from Him [Christ], as the Letter to the Ephesians and the Letter to the Colossians, in particular, tell us; Mary, too, is everything she is through Him. The word 'Co-redemptrix' would obscure this origin. A correct intention being expressed in the wrong way." (God and the world: believing and living in our time, by Pope Benedict XVI, Peter Seewald, Ignatius Press, San Francisco, 2000, p. 306
For the objection is not that the term cannot be understood in a restricted sense, but to what it most naturally conveys, that of ontologically being the mother of God, as if Mary was the author of the Divinity of Christ, yet Mary provided nothing to what makes the Son of God divine. Instead, she owes to Christ everything she is, while Catholic Mariology emphasizes what Christ owes to Mary.
For it should be understood that my objection is not to Mary being honored as the holy chosen vessel to bring forth Christ, and mothering Him according to the flesh, but to the excess ascriptions, appellations, exaltation, and adoration (and the manner of exegesis behind it), ascribed to the Catholic Mary, whether officially or by Catholics (with implicit sanction of authority), and which uniqueness and exaltation largely parallels that of Christ:
For in the the Catholic quest to almost deify Mary, it is taught by Catholics*,
as Christ was sinless, so Mary was;
as the Lord remained a virgin, so Mary;
as Christ was called the Son of God, indicating ontological oneness, so Mary is called the Mother of God (which easily infers the same, and is not the language of Scripture);
as the emphasis is upon Christ as the Creator through whom God (the Father) made all things, including Mary, so it is emphasized that uniquely to her, Jesus owes His Precious Blood, shed for the salvation of mankind, (the logic behind which can lead back to Eve);
as Catholics (adding error to error) believe Christ gave His actual flesh and blood to be eaten, so it is emphasized that Mary gave Him this, being fashioned out of Mary's pure blood and even being kneaded with the admixture of her virginal milk, so that she can say, "Come and eat my bread, drink the wine I have prepared" (Prov. 9:5);
as Scripture declares that Christ suffered for our sins, so Mary is said to have done so also;
as Christ saves us from the condemnation and death resulting from the fault of Adam, so it is taught that man was condemned through the fault of Eve, the root of death, but that we are saved through the merits of Mary; who was the source of life for everyone.
as the Lord was bodily ascended into Heaven, so Mary also was;
as Christ is given all power in heaven and in earth, so Mary is surpassing in power all the angels and saints in Heaven.
as Christ is the King of the saints and over all kings, (Rv. 15:3; 17:14; 19:16) so Mary is made Queen of Heaven and the greatest saint, and that Next to God, she deserves the highest praise;
as the Father made Christ Lord over all things, so Mary is enthroned (all other believers have to wait for their crowns) and exalted by the Lord as Queen over all things;
as Christ is highly exalted above all under the Father, so Mary is declared to be the greatest saint of all, and as having a certain equality with the Heavenly Father;
as Christ ever liveth to make intercession for the saints, so is Mary said to do so;
as all things come from the Father through the Son, so Mary is made to be the dispenser of all grace;
as Christ is given all power on Heaven and on earth, Mary is said to have (showing some restraint) almost unlimited power;
as no man comes to the Father but through the Son, so it is taught that no one can come to the Son except through Mary in Heaven;
and as the Lord called souls to come to Him to be given life and salvation, so (in misappropriation of the words of Scripture) it is said of Mary, He that shall find me shall find life, and shall have salvation from the Lord; that through her are obtained every hope, every grace, and all salvation. For this is His will, that we obtain everything through Mary.
And as Christ is given many titles of honor, so Mary also is, except that she is honored by Catholics with more titles than they give to the Lord Himself!
*Catholic ascriptions to Mary supplementary to this link .
And Cardinal Newman exuded,
He might have endued that being, so created, with a richer grant of grace, of power, of blessedness: but in one respect she surpasses all even possible creations, viz., that she is Mother of her Creator. . What outfit of sanctity, what fullness and redundance of grace, what exuberance of merits must have been hers,... St. Cyril, too, at Ephesus, "Hail. Mary, Mother of God,...through Whom the Holy Trinity is sanctified . . . through whom Angels and Archangels rejoice, devils are put to flight.. (Works taken from "Letter to the Rev. E. B. Pusey" contained in Newman's "Difficulties of Anglicans" Volume II); http://www.fordham.edu/halsall/mod/newman-mary.asp
I forget that many Protestants seem to think that Catholics believe that Mary gave birth to the eternal Godhead.
We don’t.
Yet Catholics are right in calling her The Mother of God, since Jesus is God and she is His Mother, It’s as simple as that. We are not responsible for Protestant misperceptions of Mary’s titles.
Mary is also the Queen of Heaven, as Scripture clearly indicates.
If you remove the artificially-imposed chapters and verse numbers in Scripture, these verses appear consecutively:
“Then Gods temple in heaven was opened, and within his temple was seen the ark of his covenant. And there came flashes of lightning, rumblings, peals of thunder, an earthquake and a severe hailstorm. A great sign appeared in heaven: a woman clothed with the sun, with the moon under her feet and a crown of twelve stars on her head.”
This is the woman whose Son (Jesus) would rule with an iron rod.
We see through typology that the Ark AND this crowned woman in heaven is Mary.
The Ark contained Aaron’s staff, representing the priesthood, manna, the “bread from heaven,” and the 10 Commandments, all of which serve as types for Jesus, who is eternal High Priest, the bread of life (John 6), and the Eternal Word. The Ark itself is a type for Mary, since she contained Jesus.
***
The title of Co-Redemptrix is correct, when properly understood, but confusing to the ignorant, for the reasons that the pope specified. What does that prove?