It made 14x as much for the US economy (including inspiring American children, excluding inspiring other children/nations). Can that sort of success ever be considered a waste over a long enough timeframe?
Over the short term, that's a great success. But over the long term (e.g., 50 years), it's only a 5.4% return. The S&P or DJIA, for example, had 7% returns over the same timeframe.
(Of course the two are not directly comparable, I'm just pointing out that "14x returns over unspecified timeframe" is a faulty argument.)
I think the inspiration point is a great one, if difficult to quantify. The American space program fostered a scientific literacy and pop-culture faith in the pursuit of engineering for surmounting important problems. And despite being a national program in a Cold War context, the success of the Apollo missions was bigger in scope than the US - it was a victory for all humans. We'd do well to cultivate these attitudes again.
The kind of accounting you need to do to arrive at that 14x figure would get you arrested if you put it in a corporate quarterly report, and anyway it totally ignores lost opportunity costs.
(Of course the two are not directly comparable, I'm just pointing out that "14x returns over unspecified timeframe" is a faulty argument.)