Conversation so far:
What was Neil Diamond's first album of the 1990s?
Lovescape
What was significant about the 90s for Neil Diamond?
The 1990s saw a resurgence in Neil Diamond's popularity.
Did Neil Diamond do any touring or live performances?
In 1992, Neil Diamond performed for President George H.W. Bush's final Christmas in Washington NBC special.

Question: What did he sing at the Bush special?
Self-contained rewrite: What did Neil Diamond sing at the Bush special?