To summarize what you have said: "St John mentions a war between the devil and Christians, therefore the devil is only seeking to harm Christians."
This is the fallacy of hasty generalization. Just because St John mentions a war between the devil and the saints does not mean that the devil is also not leading astray, further perverting and destroying mankind as a whole too.
St. Paul speaks of the wicked Jєωs that they are "contrary to all men":
"Who both killed the Lord Jesus, and their own prophets, and have persecuted us; and they please not God, and are contrary to all men: Forbidding us to speak to the Gentiles that they might be saved, to fill up their sins alway: for the wrath is come upon them to the uttermost."
How much more then is the spiritual father of those wicked Jєωs the devil contrary to all men?
I didn't downvote you. I don't mind honest discussion but you misunderstand me.
You could argue that Satan like the Jєωs are at war with all humanity, but with a specific reason and goal
We were discussing if St Jerome's DR translation about "THE WOMAN" crushing Satan's head is correct and St John shows us that it is.
St John doesn't just "mention war between the devil and Christians".
He is specifically speaking about enmity between Satan and "THE WOMAN"
from Genesis 3 which he quotes verbatim.
He explains again and again who "THE WOMAN" of Geneis 3 is in Apocalypse 12.
A Queen with a crown of stars appears in Heaven and gives birth:
 And she brought forth a man child, who was to rule all nations with an iron rod: and her son was taken up to God, and to his throne.
Would that Queen in Heaven be Eve? Would her man child be Abel? Is Abel to rule all nations? Is Abel taken up to God to his throne?
Clearly that is Mary and Jesus, right?
St John says several times that Satan is at enmity with the WOMAN (just like Gen 3) and is angry at her
and does war with her.
Why is he so angry with her?
What exactly did she
do to Satan anyway?
 And when the dragon saw that he was cast unto the earth, he persecuted the woman,
who brought forth the man child
So Satan persecutes Mary?
Why would he want to persecute Mary
What on earth did she
do to him?
 And the dragon was angry against the woman
: and went to make war with the rest of her seed
, who keep the commandments of God, and have the testimony of Jesus Christ.
Man...once again, Satan is really angry with "THE WOMAN"
and clearly that woman is Mary.
Why is Satan so angry with Mary?
Out of all of humanity, why do you think Satan is angry against her
What exactly did she
do to Satan?
And who exactly are her seed
Are her seed
all of humanity?
Why does Satan specifically wage war against her seed
Are you one of her seed
How do you become one of her seed?
Are her seed
What is the difference between her seed
and Eve's decendants?
Note: Eve doesn't have "seed". Adam does. Further evidence that the enmity between Satan and the "WOMAN's" seed in Gen 3 is referring to Mary.
"Identification of the "seed of the woman" with Jesus goes back at least as far as Irenaeus (180 AD), who along with several other Church Fathers regarded this verse as "the first messianic prophecy in the Old Testament". Serapion, the Bishop of Thmuis, wrote the following:
The woman does not have seed, only man does. How then was that (Gen 3:15) said of the Woman? Is it not evident that there is here question of Christ, whom the holy Virgin brought forth without seed? As a matter of fact, the singular is used, "of the seed," and not the plural, "of the seeds." The seed of the woman is referred to again in Revelation 12:17."
What did Satan say to God? No. My will be done.
What did Eve say to God? No. My will be done.
Satan seduced Eve but she consented with her free will.
Eve and all of her descendants
are on the side of Satan from then on.
Satan has Eve and her descendants "in the bag" so to speak.
"Game over. I win. Hehe."
What did Mary say to God? "Yes, Lord. Thy will be done."Her seed
does likewise.Her seed
are no longer on the side of Satan.
Mary is the "New Eve".
Her FIAT reversed Eve's "my will be done".Without Mary's "yes" there would be no Jesus and no Christians.
Do the Jєωs want anyone to become one of her seed
Are the Jєωs like Satan at enmity with Mary and her seed
Can they try to do a preemptive strike against her seed
Are they simply at war with Eve and all humanity
or are they more specifically
at war with "THE WOMAN" (Mary) and
those who will become one of her seed
They are "contrary to all men"
but with a specific goal in mind.
They, like Satan, do not want humanity to become the seed of Mary
.Her fiat, her "yes" crushed Satan's head
and he is forever at warWITH HER
and her seed
Here is more:
[color=rgba(0, 0, 0, 0.87)]Mary prophesied in the Old Testament
[color=rgba(0, 0, 0, 0.87)]The Old Testament refers to Our Blessed Lady both in its prophecies and its types or figures.
[color=rgba(0, 0, 0, 0.87)]The first prophecy referring to Mary is found in the very opening chapters of the Book of Genesis (3:15): "I will put enmities between thee and the woman, and thy seed and her seed; she shall crush thy head, and thou shalt lie in wait for her heel." This rendering appears to differ in two respects from the original Hebrew text:
[color=rgba(0, 0, 0, 0.87)](1) First, the Hebrew text employs the same verb for the two renderings "she shall crush" and "thou shalt lie in wait"; the Septuagint renders the verb both times by terein, to lie in wait; Aquila, Symmachus, the Syriac and the Samaritan translators, interpret the Hebrew verb by expressions which mean to crush, to bruise; the Itala renders the terein employed in the Septuagint by the Latin "servare", to guard; St. Jerome  maintains that the Hebrew verb has the meaning of "crushing" or "bruising" rather than of "lying in wait", "guarding". Still in his own work, which became the Latin Vulgate, the saint employs the verb "to crush" (conterere) in the first place, and "to lie in wait" (insidiari) in the second. Hence the punishment inflicted on the serpent and the serpent's retaliation are expressed by the same verb: but the wound of the serpent is mortal, since it affects his head, while the wound inflicted by the serpent is not mortal, being inflicted on the heel.
[color=rgba(0, 0, 0, 0.87)](2) The second point of difference between the Hebrew text and our version concerns the agent who is to inflict the mortal wound on the serpent: our version agrees with the present Vulgate text in reading "she" (ipsa) which refers to the woman, while the Hebrew text reads hu' (autos, ipse) which refers to the seed of the woman. According to our version, and the Vulgate reading, the woman herself will win the victory; according to the Hebrew text, she will be victorious through her seed. In this sense does the Bull "Ineffabilis" ascribe the victory to Our Blessed Lady. The reading "she" (ipsa) is neither an intentional corruption of the original text, nor is it an accidental error; it is rather an explanatory version expressing explicitly the fact of Our Lady's part in the victory over the serpent, which is contained implicitly in the Hebrew original. The strength of the Christian tradition as to Mary's share in this victory may be inferred from the retention of "she" in St. Jerome's version in spite of his acquaintance with the original text and with the reading "he" (ipse) in the old Latin version.
[color=rgba(0, 0, 0, 0.87)]As it is quite commonly admitted that the Divine judgment is directed not so much against the serpent as against the originator of sin, the seed of the serpent denotes the followers of the serpent, the "brood of vipers", the "generation of vipers", those whose father is the Devil, the children of evil, imitando, non nascendo (Augustine).  One may be tempted to understand the seed of the woman in a similar collective sense, embracing all who are born of God. But seed not only may denote a particular person, but has such a meaning usually, if the context allows it. St. Paul (Galatians 3:16) gives this explanation of the word "seed" as it occurs in the patriarchal promises: "To Abraham were the promises made and to his seed. He saith not, and to his seeds, as of many; but as of one, and to his seed, which is Christ". Finally the expression "the woman" in the clause "I will put enmities between thee and the woman" is a literal version of the Hebrew text. The Hebrew Grammar of Gesenius-Kautzsch  establishes the rule: Peculiar to the Hebrew is the use of the article in order to indicate a person or thing, not yet known and not yet to be more clearly described, either as present or as to be taken into account under the contextual conditions. Since our indefinite article serves this purpose, we may translate: "I will put enmities between you and a woman". Hence the prophecy promises a woman, Our Blessed Lady, who will be the enemy of the serpent to a marked degree; besides, the same woman will be victorious over the Devil, at least through her offspring. The completeness of the victory is emphasized by the contextual phrase "earth shall thou eat", which is according to Winckler  a common old-oriental expression denoting the deepest humiliation .