The OP's question is, "What is the meaning of the 3 plucked horns?"
In order to address that question we first must determine what the meaning of the word "horns", and then determine what "3 plucked horns" mean. In the process I will discuss whether it relates to the Antichrist as a prophetic interpretation, and address his secondary question of whether or not the horns of Dan. 11:40-45 satisfy the interpretation of Dan. 7:8.
Interpretive Meaning of 'Horns'
To begin to understand what "horns" means in context with the passage, we must start with verse 1,
"In the first year of Belshazzar king of Babylon Daniel had a dream
and visions of his head upon his bed: then he wrote the dream, and
told the sum of the matters."(KJV)
Since he is describing his dream, we must be careful to understand that "dreams" contain symbols which are images that convey a special meaning that in many cases is different from it's normal (historical/grammatical) interpretation.
In this particular passage, the angel interprets them for us: (vs 17, KJV)
"These great beasts, which are four, are four kings, which shall arise
out of the earth."
"Kings" here must be understood as "Kingdoms", rather than a succession of monarchs: the reason is that in Daniel's interpretation of Nebuchadnezzar's dream in chapter 2, a similar progression of "kingdoms" is described, each with particular characteristics and assigned a particular metal(gold, silver, brass, iron). Daniel's 4th Beast, from which the "horns" in question emanate from, is described as "iron teeth", which relates to the kingdom of "iron".
Therefore, the "beasts" of Daniel are a succession of kingdoms which start with Babylon(the lion): then Mede-Persia(the bear), Greece(the leopard), and finally Rome(the terrible beast that crushes with iron teeth). This progression follows the progression of the statue of Nebuchadnezzar, in which Nebuchadnezzar, representing the gold head(Babylon), is followed by Mede-Persia, then Greece, then Rome, then the Holy Roman Empire(mixture of clay and iron), which culminates into the 10 toe nations.
In this particular instance, the "horns" which grow out of the Roman head are described as "kingdoms", but are best understood as "nations": since Rome disintegrated as a world power, it's colonies(those it had conquered from native tribes, not previous world kingdoms such as Greece, Persia, Egypt, etc.) became nations in their own right. England, Spain, France were once former colonies of Rome, yet became nations(first kingdoms) after Rome fell. Thus, the same progression of kingdoms described in Daniel 2 is also described in Daniel 7, except they are described as "beasts" since they collectively oppose the Kingdom of God, resulting in God's Kingdom being established ("an everlasting dominion"-vs 14) in which the Son of man will reign over them after their dominion is destroyed. Since this event hasn't yet occurred, we see "10 kingdoms" still ruling in this present day-correlating to the 10 toes.
The 3 Plucked Horns
Since the "horns" are Roman colonies, we must look to the colonies which survived the Fall of Rome to determine their fate, as 3 appear to be "plucked up" to make room for the "little horn" of vs 8.
What is apparent is that these "nations' were not removed; they exist within their relative geographical boundaries since the Fall of Rome. Their languages, customs, and national characteristics remain unique, in spite of centuries of assimilation. So, how were they "plucked up" to make room for the little horn?
Several of these nations had colonies: most notably England, Spain, and France. Some they seized from failed states(India, SE Asia, Africa) in an attempt to 'Christianize' them; one in particular was a vast 'unknown' land where indigenous peoples roamed, yet held no central government or ruling council; the land was "up for grabs" so to speak. The continent was North America, and the land is now known as the United States. The original colonists came from England, yet both France and Spain made territorial claims, and sent colonists to the New World. In the resulting wars, England, France, and Spain were driven out to make room for a "diverse" nation; one that was not identified with a national heritage or culture, took great exception not to be labeled as a "monarchy", and established itself as a Constitutional Republic, modeled after Plato's Republic. It welcomed all the nations of the world, so that no one nation can claim dominance as in the rest of the world-it truly is multi-cultural.
Thus, along with the other 10 horns, it reigns as a 'little horn'; little in the effect of it's recent entrance on civilization, and it's territorial claims beyond it's borders, yet it is the apogee and epitome of man's progress, and "boasts" great claims over disease, social engineering, scientific discovery, space exploration, wealth that the rest of the world marvels over. It is the imagination and entertainment capital of the world. It has the "eyes of man", for like the "eyes of God", attempts to "see all, know all". Since it's complexion is composite, and not one nationality, it takes the best that all of man has to offer and calls it it's own.
Is this "little horn" the Antichrist?
The identity of the "Antichrist" has been discussed thoroughly in numerous posts I have written: one of them is this. Since this is a lengthy discussion, not germane to the OP's query I will simply say that it is a significant part of the many nations that comprise the Antichrist.
2 Scriptures to consider:
And it was given unto him to make war with the saints, and to overcome
them: and power was given him over all kindreds, and tongues, and
nations.(Rev. 13:7, KJV)
The US indeed influences the entire earth, but does not have power over the entire earth.
Another Scripture is Rev. 17:10-12(KJV),
And there are seven kings: five are fallen, and one is, and the other
is not yet come; and when he cometh, he must continue a short space.
11 And the beast that was, and is not, even he is the eighth, and is
of the seven, and goeth into perdition.
12 And the ten horns which thou sawest are ten kings, which have
received no kingdom as yet; but receive power as kings one hour with
The beast/Antichrist WAS and is not. The US didn't exist until the 18th Century
Are these 'plucked horns' the same as Dan. 11:40-45?
Simple answer: no.
The North, South, East, and West directly relate to the "pleasant land". In Dan. 8:8-9(KJV), it says,
Therefore the he goat waxed very great: and when he was strong, the
great horn was broken; and for it came up four notable ones toward the
four winds of heaven.
9 And out of one of them came forth a little horn, which waxed
exceeding great, toward the south, and toward the east, and toward the
The "pleasant land" of course is Israel, and as the 4 Notable Horns, which were broken off when the Great Horn(Alexander the Great) died and left no heir, in which case his 4 Generals(Cassander, Lysimachus, Seleucus, and Ptolemy took control of the territory Alexander had conquered in the 4 Cardinal Directions(N,S,E,W) and their territory is all in relation to Israel. The "he" is certainly the Antichrist, who (Dan.11:37 KJV)
Neither shall he regard the God of his fathers, nor the desire of
women, nor regard any god: for he shall magnify himself above all.
This passage is at the end of a long prophetic description of what will happen during the Greek occupation, which starts at the beginning of the chapter.
In vs. 35 we read,
And some of them of understanding shall fall, to try them, and to
purge, and to make them white, even to the time of the end: because it
is yet for a time appointed.
Since in Chapter 12:1 it says,
"And at that time shall Michael stand up, the great prince which
standeth for the children of thy people: and there shall be a time of
trouble, such as never was since there was a nation even to that same
time: and at that time thy people shall be delivered, every one that
shall be found written in the book",
we have a continuous narrative from vs 36; Israel as a nation has yet to be delivered, and the verse following (vs 2), says
And many of them that sleep in the dust of the earth shall awake,
some to everlasting life, and some to shame and everlasting contempt.
Since this is talking about the "Parousia", this hasn't happened yet.
The "horns" are the outgrowth of Rome; the "South, North, and East" relate to the Greek Empire that was split up after Alex's death. None of these "horns" are the nations in question-in fact, they are to the west. Therefore the premise that these 'might' be the horns that are plucked is incorrect.
The "3 Plucked Horns" are Spain, France, and England, former colonies of Rome which became 1st kingdoms, then nations of their own right. The United States, which was colonized by these kingdoms, "plucked up" their kingdoms through conquest, and became a 'diverse' kingdom, one that from it's inception was ruled as a Constitutional Republic. The "N, S, E" kingdoms of Dan. 11:40-45 cannot be a part of them, since they were originally empires of their own right and later kingdoms of the breakup of the Greek Empire-not the Roman Empire.