Perhaps it should be noted that the chair of the Edmund Burke Foundation, which is behind National Conservatism, is one Yoram Hazony, an academic from Israel, the home of - and template for - unabashed ethno-nationalism:

https://nationalconservatism.org/people/

I am not sure how National Conservatism relates to Burkian conservatism, if at all.

Is NC a flash in the pan, a loony extreme, or should we take it seriously?

After all, there was a time when UKIP wasn't taken seriously and look where that got us.

After the inevitable failure of the next Labour Government, will NC be the rough beast, waiting in the wings, slouching to be born?