"An expression at Romans 13:1 designating human governmental authorities...Since the governmental authorities render valuable services to ensure the safety, security, and welfare of their subjects, they are entitled to taxes and tribute in compensation for their services."
As we just read, the earmark of a "superior authority" is a governmental authority that is entitled taxes. Though the UN does have an amount of power in the world, it does not require direct taxes therefore it is not Caesar.
"3W" contends that
"3W" tells us Some claim that the Watchtower publications teach that the UN is ‘the unclean thing’ and that the scripture which says, “quit touching the unclean thing” at 2 Corinthians 6:17 has been applied to the UN by the publications. This is completely false. No publication has ever taught that the UN is “the unclean thing” as discussed at 2 Corinthians 6:17. Before we get into discussing this statement, I think it would be pertinent to bring up the 1960's "Malawi Massacre" and compare it to the Watchtower's associated status with the UN. Jehovah's Witnesses as a whole use their "politically neutral" stance as one of their defining factors of being the "true religion". They have maintained this throughout many decades, and in many of their writings. In one of their magazines (1968 Watchtower February 1st p. 17-19) they printed an article where scores of JW's were beaten, raped, and killed simply because they refused to buy a 25 cent Malawi Congress Party membership card. A card that they were required to buy but they weren't required to vote. To read the whole context of this article CLICK HERE. Scores of JW's lost their life because of the fact that they were taught to stay politically neutral, and at all cost. There was another Watchtower article (1976 Watchtower October 15th pages 632-636) that came out later and referenced this incident. A snippet from the article says:
As Jehovah's Witnesses they value their relationship to God and Christ above everything else. Were they to identify themselves as giving unquestioning support to any political arrangement... Any act on their part that would indicate otherwise, therefore, would be an act of disloyalty. Such an act would be taking away from God and Christ their rightful due and would be worship to the "wild beast." No matter how insignificant the act required may seem, a Christian's engaging in such worship would mean his being disloyal to God and Christ.
Now back to the statement of whether the WBTS views the UN as the "unclean thing". "3W" maintains that the WBTS has never specifically called the UN the "unclean clean", which is true in the strictest sense. However, the Watchtower has lumped worldly political, financial, and governmental agencies of the world into ONE category. Which category? Well, the unclean thing. Read the 1952 Watchtower January 15th page 54 below...
Besides, note the political, financial and moral corruption in the governments of the world. Particularly in recent months have investigations in Washington revealed a state of corruption that stinks to heaven. Why should Christians want to have anything to do with such an unclean organization? Counsel the Scriptures: “Get out from among them, and separate yourselves, . . . and quit touching the unclean thing.” Surely it would be folly for Christians to try to sew the new patch of Christian principles on that old garment of corrupt democracy. Christians, therefore, who understand God’s Word shun political ambassadors.So if the UN is a government as "3W" has asserted in this chapter, then the WBTS does indeed need to "quit touching the unclean thing", which includes the United Nations.