Interesting post.
A Question for Undisfellowshipped and others:
On page 2 of this thread you quoted from the Isaiah book, and there are 2 expressions that caught my eye, that I have highlighted in red
Isaiah's Prophecy - Light For All Mankind Book, Volume 1 (2000), Pages 153-154:
20 Whom will Jehovah use to discipline rebellious Christendom? We find the answer in the 17th chapter of Revelation. There we are introduced to a harlot, "Babylon the Great," representing all the world’s false religions, including Christendom. The harlot is riding a scarlet-colored wild beast that has seven heads and ten horns. (Revelation 17:3, 5, 7-12) The wild beast represents the United Nations organization.* [FOOTNOTE SAYS: Additional information regarding the identity of the harlot and the scarlet-colored wild beast is found in chapters 34 and 35 of the book Revelation—Its Grand Climax At Hand!, published by the Watchtower Bible and Tract Society of New York, Inc.] Just as the ancient Assyrian destroyed Samaria, the scarlet-colored wild beast "will hate the harlot and will make her devastated and naked, and will eat up her fleshy parts and will completely burn her with fire." (Revelation 17:16) Thus the modern-day Assyrian (nations associated with the UN) will deal Christendom a mighty blow and will crush her out of existence.
Isaiah's Prophecy - Light For All Mankind Book, Volume 1 (2000), Pages 345-346:
7 How does Isaiah’s prophecy apply in our day? The spiritually sick nation of Israel can be compared to unfaithful Christendom. Just as Jehovah used Assyria as a "rod" to punish Israel, so he will use a "rod" to punish Christendom—as well as the rest of the world empire of false religion, "Babylon the Great." (Isaiah 10:5; Revelation 18:2-8) That "rod" will be member nations of the United Nations—an organization pictured in Revelation as a seven-headed, ten-horned, scarlet-colored wild beast.—Revelation 17:3, 15-17.
Unfortunately I no longer have the publications to go back and research myself, but if the 1988 Revelation book contained little or no mention of the UN, and the quotes you provided from the 2000 Isaiah book mentions ' nations that are members of the UN ' could it be that as early as 1987 the GB 's hard line against the UN was going through a metamorphosis....... shifting suspicion from the UN to its member nations ?