America's most popular living classical composer makes an interesting comment in a New York Times book review of Camille Paglia:
The achievement of [George] Lucas, like that of Disney, is indisputably a defining element of American culture. But no amount of apotheosis and breathless encomium will elevate it to be other than exactly what it is — entertainment. To see George Lucas as the “greatest living artist” is to repeat an error especially common among Americans, which is to measure an artwork’s importance by its reach rather than its depth. Paglia, who knows her Emily Dickinson and her Kafka (both artists with zero “fan base” in their lifetimes), has journeyed to the wrong continent, and what she has found glittering there is fool’s gold.
Ok, having quoted that, America's most popular living classical composer may instead be John Williams.
The greatest works of John Adams are without argument better than those of John Williams (Nixon in China vs. Star Wars!). But in the second tier where reach and depth get murky, Williams' works will outlast Adams'.
This is a long, roundabout way of saying Hallelujah Junction won't be part of the American canon and John Williams is better than George Lucas. H.J., the book is recommended, though.
I have no opinion to offer on Camille Paglia, which is probably her worst nightmare.