50 years of highways

Ooh, this looks like an interesting article - it's apparently a biography of the nation's interstate system, and for me it's pure mapporn! *grin* However, the following severely mangled nest of mixed metaphors made me cringe.

So it's hard to believe that America's freeway system turns 50 this summer — a chronological blip on the tectonic plates too slight for a spectrometer, but in the life of our republic, a golden anniversary.

*shudder*