“... provoking British academic Binoy Kampmark to label Burnham as “the first neoconservative.”
A technicality. Burnham made the journey, but he was by no means “neocon”. He was often right, occasionally wrong, and always challenging. He provided the framework for people like Joe Sobran, Paul Gottfried, Sam Francis, and others who ended up being right about pretty much everything.
He would not be welcome at National Review in the Current Year. That goes for much of the conservative movement until about 1995.
I think that the term “neoconservative” was being used here to mean a former leftist turned conservative, as opposed to adherence to the sort of ideology that we associate with neoconservatism today.