>Apollo and Skylab

A grotesquely expensive set of jolly jaunts to the Moon followed by a few parasitical (ie, no new technology was actually built) orbital flights; which was cancelled by a USAmerican Congress which couldn't afford it & the Vietnam War at the same time. Not a NASA decision; although a study of the economics of the project would suggest that the right decision was made here.

>Clementine 2

A NRO project line vetoed by Clinton. Not a NASA project or cancellation.

>DC-X.

A USAF project dropped by the military & supported by NASA even after they decided that powered landing wasn't the way to go - an assessment rather supported by the unit's crash & burn a few week's later... may be interpreted as a NASA cancellation; but that's stretching it. A fairly ordinary technology appallingly hyped by the military during Star Wars I.

Robert