Tsar bomb.
.....apart from not admitting failure, by not actually being able to land?No , perfectly logical . America sees itself as much greater than anyone else on the planet and it has an almost irrational fear of anyone else having the lead on them . Yes Russia did build the Tsar bomb but the US just had to build more bombs than the Soviets . Even now they spend more than any other country on defence .
Simple fact is that this conspiracy falls apart because the US would have very little to gain by faking the landings.