There's the problem -- conflating Fascism and National Socialism.  The  one 
has little to do with the other, beyond the focus of both on state  
control.  Both were actually praised at the time by the Left.   And note that 
Einzig's book came out in 1933!!!
 
As to Progressivism, there is nothing liberal about that philosophy -- it  
was born of intolerance.  Eugenics policies, immigration restrictions, the  
need to prevent "race suicide," were Progressive notions.  The writings of  
Edward Ross, Richard Ely, et al. display gross intolerance, and advocate  
policies, political and economic, consistent with what would become known  
decades later as Fascism.
 
Charles McCann