"Lesson 1: Public interest is not sustainable for decades
...
Al Gore confirmed this fact when he said: “Ten years is about the maximum time that we, as a nation, can hold a steady aim and hit our target.” So, the first lesson we could learn from the last thirty years of spaceflight is that public interest is not sustainable for decades."

Or maybe ten years is about as long as lies lasts.

"Lesson 2: It’s dangerous to oversell a program

When President Nixon announced the Space Shuttle program in 1972, NASA envisioned a very affordable ($25 million a flight) and routine (50 missions a year) airline-type access to space. Even in 1982, some 500 flights were scheduled for the first twelve years of Shuttle operations. Well, after thirty years of flight, we’ll had achieved less than 135 missions for a program that cost at least $150 billion (that’s more than a billion dollars per flight). Thus, one the main lessons to be learned from the Space Shuttle is that it’s dangerous to oversell a program."

Hmm. The Saturn V program delivered more payload to LEO than the Shuttle [about 4 times more and could get things to the Moon and/or Mars]. Cost about 1/2 per flight than than the Shuttle. And the Saturn V program lasted for about a decade. The Saturn V program wasn't oversold- it was an amazing vehicle- and particularly amazing considering the govt built it.
The Shuttle was oversold, oversold, oversold. It was a utter failure and was sold and sold and sold as this wonderful creature. The Shuttle program has last for 3 decades. So dangerous in what way?
Certainly dangerous in terms of wasting tax dollar. And certainly dangerous in terms of stalling progress in opening the space frontier. But not dangerous in terms keeping a job program.