You don’t think there was any consultation between JFK and NASA before he gave that speech? A simple search for more information provides this. Kennedy asked J

You don’t think there was any consultation between JFK and NASA before he gave that speech? A simple search for more information provides this. Kennedy asked Johnson to consult with NASA. Johnson consulted with officials of the National Aeronautics and Space Administration (NASA). Its new administrator, James E. Webb, told him that there was no chance of beating the Russians to launching a space station, and he was not certain that NASA could orbit a man around the Moon first, so the best option would be to attempt to land a man on the Moon. This would also be the most expensive option; Webb believed it would require $22 billion (equivalent to $166 billion in 2022) to achieve it by 1970. Johnson also consulted with Wernher von Braun; military leaders, including Lieutenant General Bernard Schriever; and three business executives: Frank Stanton from CBS, Donald C. Cook from American Electric Power, and George R. Brown from Brown & Root. JFK was stating an experts opinion in a speech not spitballing random estimates that were changing yearly in order to make him and the US seem awesome.