Gibbon on the other hand in 6 volumes wrote a work that will probably be in print until Western Civilisation sinks into the dust.
So - kinda depends I would say.
As a side note, I also find it amusing that you expect Churchill's "aura" to fade. If current trends are any indication, he's moving toward folk tale hero status rather than the slow march toward obscurity (with multiple appearances in Doctor Who and other fictional media). In my opinion, the only thing that potentially stands in the way is a possible upheaval of the Western power base or an Alexandria style purge of knowledge. I say this as a US citizen who is much too young to remember the fall out of the war, much less the war itself.
I've never heard this figure of speech and Google isn't turning anything up. What does it mean?