I read somewhere that the Apollo 11 moon landing is still one of the most-watched live tv events in history, had something like 650 million viewers. Through the 50s and 60s it seemed there was so much public support for NASA and the government was dumping loads of money into the space program. However, after the first three missions it was as if nothing had ever happened and nobody seemed to give a fuck anymore. I saw that viewership of the launches from that point on had steeply declined. So what happened? Is this also the reason why the Apollo program was cancelled?
" Through the 50s and 60s it seemed there was so much public support for NASA and the government was dumping loads of money into the space program."
To be blunt, this is a historic myth. To address this I'm going to pull info from this paper (it's a pdf btw) by NASA's chief historian Roger Launius.
First, one thing to keep in mind is that the NASA budget, while less than 1% of the federal budget today, in the 1960s was a bigger percentage of the overall budget (if still fairly small), approaching 3.5% in the late 1960s. In context that's also at a point where federal spending was rising fast both on other domestic programs and on the war in Vietnam (and this was beginning to be felt in increased inflation).
As a result, American public support for the space program as a whole was rather broad, but soft. For example, in 1965 about 80% of the American public favored funding space exploration (a figure that stayed remarkably level), but about one third of respondents that year wanted the budget cut (only 16% wanted it increased). Over the next four years the number wanting the budget cut increased to 40%, with those wanting it increased dipped to 14%. The space program in this period ranked in one of the top government programs to be cut, and was ranked as less important than other projects like pollution cleanup, job training, and anti-poverty programs.
The lunar program had even weaker public support. Public opposition to sending manned expeditions to the moon was higher than support in polls taken from 1961 until well after the lunar program, with the exception of October 1965. In July 1967 and April 1970, ie just before and during the Apollo missions, public opposition to manned landings exceeded 50%.
When asked specifically about Apollo you can see more of the broad-but-not-deep support. 60-80% of respondents between 1963 and 1969 said they approved of the Apollo program, while only 35-45% said the program was worth the cost (the only time a majority - 53% - of respondents said it was worth the cost was immediately after Apollo 11 in July 1969). A similar number of respondents in that same period thought the US was "spending too much on space".
In conclusion, I would directly quote Launius himself:
"These data do not support a contention that most people approved of Apollo and thought it important to explore space. The decision to proceed with Apollo was not made because it was enormously popular with the public, despite general acquiescence, but for hard-edged political reasons. Most of these were related to the cold war crises of the early 1960s, in which spaceflight served as a surrogate for face-to-face military confrontation."
I have answered this before here.