Many possible reasons at the human level. At the spiritual level, maybe just one - destroying the Jews is Satan's only hope to prevent his fate? If there's a prerequisite for the Lords return that rests solely on the Jewish nation calling out to Jesus as Christ, then Satan may reason he can prevent this if there is no Jew left to call out.
The prerequisite verses, notice the "till" in both:
For I say unto you, Ye shall not see me henceforth, till ye shall say, Blessed is he that cometh in the name of the Lord. Matthew 23:39
I will go and return to my place, till they acknowledge their offence, and seek my face: in their affliction they will seek me early. Hosea 5:15
So whatever motivated Hitlers hate in his own mind, we know Satan stirred it up for his own purpose. Even all the hate in the world today, motivated by various reasons at the human level (politics, race, class, gender, etc...), could be ultimately laser-focused against Satan's real target - the Jew. It wouldn't be a bad strategy, but will fail.
Therefore rejoice, ye heavens, and ye that dwell in them. Woe to the inhabiters of the earth and of the sea! for the devil is come down unto you, having great wrath, because he knoweth that he hath but a short time. And when the dragon saw that he was cast unto the earth, he persecuted the woman which brought forth the man child. Revelation 12:12-13
Here's a sample of God's judgement on the Jews in OT times.
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Shall a trumpet be blown in the city, and the people not be afraid? Shall there be evil in a city, and the Lord hath not done it?” Amos 3:6 (KJV 1900)
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I form the light, and create darkness: I make peace, and create evil: I the Lord do all these things.” Isaiah 45:7 (KJV 1900)
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But the Spirit of the Lord departed from Saul, and an evil spirit from the Lord troubled him.” 1 Samuel 16:14 (KJV 1900)
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Behold, I will bring evil upon thee, and will take away thy posterity, and will cut off from Ahab him that [bless and do not curse][bless and do not curse][bless and do not curse][bless and do not curse]eth against the wall, and him that is shut up and left in Israel,” 1 Kings 21:21 (KJV 1900)
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And the king of Israel said unto Jehoshaphat, There is yet one man, Micaiah the son of Imlah, by whom we may inquire of the Lord: but I hate him; for he doth not prophesy good concerning me, but evil. And Jehoshaphat said, Let not the king say so.” 1 Kings 22:8 (KJV 1900)
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But he said unto her, Thou speakest as one of the foolish women speaketh. What? shall we receive good at the hand of God, and shall we not receive evil? In all this did not Job sin with his lips.” Job 2:10 (KJV 1900)
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He cast upon them the fierceness of his anger, Wrath, and indignation, and trouble, By sending evil angels among them.” Psalm 78:49 (KJV 1900)
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Yet he also is wise, and will bring evil, And will not call back his words: But will arise against the house of the evildoers, And against the help of them that work iniquity.” Isaiah 31:2 (KJV 1900)
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Therefore shall evil come upon thee; thou shalt not know from whence it riseth: And mischief shall fall upon thee; thou shalt not be able to put it off: And desolation shall come upon thee suddenly, which thou shalt not know.” Isaiah 47:11 (KJV 1900)
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Out of the mouth of the most High proceedeth not evil and good?” Lamentations 3:38 (KJV 1900)
Cannibalism
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And I will cause them to eat the flesh of their sons and the flesh of their daughters, and they shall eat every one the flesh of his friend in the siege and straitness, wherewith their enemies, and they that seek their lives, shall straiten them.” Jeremiah 19:9 (KJV 1900)
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So that he will not give to any of them of the flesh of his children whom he shall eat: because he hath nothing left him in the siege, and in the straitness, wherewith thine enemies shall distress thee in all thy gates.” Deuteronomy 28:55 (KJV 1900)
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The hands of the pitiful women have sodden their own children: They were their meat in the destruction of the daughter of my people.” Lamentations 4:10 (KJV 1900)
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And ye shall eat the flesh of your sons, and the flesh of your daughters shall ye eat.” Leviticus 26:29 (KJV 1900)
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Therefore the fathers shall eat the sons in the midst of thee, and the sons shall eat their fathers; and I will execute judgments in thee, and the whole remnant of thee will I scatter into all the winds.” Ezekiel 5:10 (KJV 1900)
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And ye shall eat the flesh of your sons, and the flesh of your daughters shall ye eat.” Leviticus 26:29 (KJV 1900)
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And thou shalt eat the fruit of thine own body, the flesh of thy sons and of thy daughters, which the Lord thy God hath given thee, in the siege, and in the straitness, wherewith thine enemies shall distress thee:” Deuteronomy 28:53 (KJV 1900)
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And he shall snatch on the right hand, and be hungry; And he shall eat on the left hand, and they shall not be satisfied: They shall eat every man the flesh of his own arm:” Isaiah 9:20 (KJV 1900)
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“And I will make void the counsel of Judah and Jerusalem in this place; and I will cause them to fall by the sword before their enemies, and by the hands of them that seek their lives: and their carcases will I give to be meat for the fowls of the heaven, and for the beasts of the earth. And I will make this city desolate, and an hissing; every one that passeth thereby shall be astonished and hiss because of all the plagues thereof. And I will cause them to eat the flesh of their sons and the flesh of their daughters, and they shall eat every one the flesh of his friend in the siege and straitness, wherewith their enemies, and they that seek their lives, shall straiten them.” Jeremiah 19:7–9 (KJV 1900)
“Therefore the fathers shall eat the sons in the midst of thee, and the sons shall eat their fathers; and I will execute judgments in thee, and the whole remnant of thee will I scatter into all the winds. Wherefore, as I live, saith the Lord God; Surely, because thou hast defiled my sanctuary with all thy detestable things, and with all thine abominations, therefore will I also diminish thee; neither shall mine eye spare, neither will I have any pity. A third part of thee shall die with the pestilence, and with famine shall they be consumed in the midst of thee: and a third part shall fall by the sword round about thee; and I will scatter a third part into all the winds, and I will draw out a sword after them. Thus shall mine anger be accomplished, and I will cause my fury to rest upon them, and I will be comforted: and they shall know that I the Lord have spoken it in my zeal, when I have accomplished my fury in them.” Ezekiel 5:10–13 (KJV 1900)
“And if ye will not be reformed by me by these things, but will walk contrary unto me; Then will I also walk contrary unto you, and will punish you yet seven times for your sins. And I will bring a sword upon you, that shall avenge the quarrel of my covenant: and when ye are gathered together within your cities, I will send the pestilence among you; and ye shall be delivered into the hand of the enemy. And when I have broken the staff of your bread, ten women shall bake your bread in one oven, and they shall deliver you your bread again by weight: and ye shall eat, and not be satisfied. And if ye will not for all this hearken unto me, but walk contrary unto me; Then I will walk contrary unto you also in fury; and I, even I, will chastise you seven times for your sins. And ye shall eat the flesh of your sons, and the flesh of your daughters shall ye eat. And I will destroy your high places, and cut down your images, and cast your carcases upon the carcases of your idols, and my soul shall abhor you. And I will make your cities waste, and bring your sanctuaries unto desolation, and I will not smell the savour of your sweet odours. And I will bring the land into desolation: and your enemies which dwell therein shall be astonished at it. And I will scatter you among the heathen, and will draw out a sword after you: and your land shall be desolate, and your cities waste.” Leviticus 26:23–33 (KJV 1900)