This week was my niece's 7th birthday. For whatever reason, this song always makes me think of her -- I think it's the line "Maybe you'll/be President/But know right from wrong." If my memory is correct, Hail to the Thief was recorded around the time Yorke had his first child, and the album's concerns seem to be coming in part from the perspective of a parent worrying about the future of a planet he's leaving behind for his offspring.
Anyway, those are my impressions of "Sail to the Moon." Here's a superb live version ...