From the Department of State:
<< On October 12, 2017, the Department of State notified UNESCO Director-General Irina Bokova of the U.S. decision to withdraw from the organization and to seek to establish a permanent observer mission to UNESCO. This decision was not taken lightly, and reflects U.S. concerns with mounting arrears at UNESCO, the need for fundamental reform in the organization, and continuing anti-Israel bias at UNESCO.
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Pursuant to Article II(6) of the UNESCO Constitution, U.S. withdrawal will take effect on December 31, 2018. >>
https://www.state.gov/r/pa/prs/ps/2017/10/274748.htm
This is a great decision, and it is especially wonderful to read this as a message from the State Department.
In case you are wondering whether the anti-Israel is real and sufficient - here is just one illustration:
<< Submitted to UNESCO’s Executive Board by Algeria, Egypt, Lebanon, Morocco, Oman, Qatar and Sudan, the resolution on “Occupied Palestine,” which indicates that Israel has no legal or historical rights anywhere in Jerusalem, had been expected to pass, given the automatic anti-Israel majority in the 58-member body.
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The resolution indicates rejection of the Jewish state’s sovereignty in any part of Jerusalem. Israel is referred to throughout the document as the “occupying power” in Jerusalem, indicating that it has no legal or historical ties to any part of the city.
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The vote, which coincided with Israel’s Independence Day, passed with 22 countries in favor, 23 abstentions, 10 opposed, and the representatives of three countries absent.
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The 10 countries that voted against the resolution were the US, UK, Italy, the Netherlands, Lithuania, Greece, Paraguay, Ukraine, Togo, and Germany. >>
https://www.timesofisrael.com/on-independence-day-unesco-okays-resolution-ignoring-jewish-links-to-jerusalem/