In a New York Times interview in 1968, Kubrick merely referred to the satellites as "spacecraft", as does the interviewer, but he observed that the match-cut from bone to spacecraft shows they evolved from "bone-as-weapon", stating "It's simply an observable fact that all of man's technology grew out of his discovery of the weapon-tool".
Nothing in the film calls attention to the purpose of the satellites. James John Griffith, in a footnote in his book Adaptations As Imitations: Films from Novels, wrote "I would wonder, for instance, how several critics, commenting on the match-cut that links humanity's prehistory and future, can identify — without reference to Clarke's novel — the satellite as a nuclear weapon".
Arthur C. Clarke, in the TV documentary "2001: The Making Of A Myth", described the bone-to-satellite sequence in the film, saying "The bone goes up and turns into what is supposed to be an orbiting space bomb, a weapon in space. Well, that isn't made clear, we just assume it's some kind of space vehicle in a three-million-year jump cut". Former NASA research assistant Steven Pietrobon wrote "The orbital craft seen as we make the leap from the Dawn of Man to contemporary times are supposed to be weapons platforms carrying nuclear devices, though the movie does not make this clear."
The vast majority of film critics, including noted Kubrick authority Michel Ciment, interpreted the satellites as generic spacecraft (possibly Moon bound).
The perception that the satellites are nuclear weapons persists in the minds of some viewers (and some space scientists). However, due to their appearance there are statements by members of the production staff who still refer to them as weapons. Walker, in his book Stanley Kubrick, Director, noted that although the bombs no longer fit in with Kubrick's revised thematic concerns (thus becoming "red herrings"), "nevertheless from the national markings still visible on the first and second space vehicles we see, we can surmise that they are the Russian and American bombs."
Similarly, Walker in a later essay stated that two of the spacecraft seen circling Earth were meant to be nuclear weapons, after asserting that early scenes of the film "imply" nuclear stalemate. Pietrobon, who was a consultant on 2001 to the Web site Starship Modeler regarding the film's props, observes small details on the satellites such as Air Force insignia and "cannons".