Is the 'One small step for man; one giant leap for mankind' audio copyright?

I think you could be certain that, as a spokesman for NASA, (a Federal Agency), and said in the course of his employment, Neil Armstrong's ''One Small Step'' speech is not capable of being copyrighted under US Law.

In any event, if it were his composition, as a private citizen, which he was not, it would have to be proven that he wrote the speech down before he delivered it for it to be copyright.

No

If the government every claimed copyright for the original recording, it would have expired by now.

noep. that's just cruelty.
that phrase references man's first step on the moon's surface.

Only if it is part of a production with copyright and pattens approved

Yes