On the very same day that the US reportedly went to the moon the USSR was conducting an unmanned mission on the moon as well. Getting to the moon by 1969 was "easy". Getting men to the moon was the problem. The vector which had problems that you mention had the purpose of lifting a larger weight than what was already possible, with the goal of even sending probes (obviously) to Mars.
LATER EDIT: For those with a mind open to doubt, I suggest beginning from this site: