The use of the word barbarian is not rhetorical nor is it intended to be provocative. It means what it says. Sure, anti-marketeers like Cox, Tanner, Santamaria, Krygier et al. are not themselves barbarians but they pursue policies that taken to their logical conclusion would eventually lead to barbarism by ruining the economy. Nazi Germany and Argentina's Peronist legacy provide bloodstained examples of what I mean. Let us take her last piece of nonsense first.
Totalitarian states are anti-market.
Every totalitarian is viciously opposed to the free market because he knows that it is incompatible with his belief that society is a kind of social entity that can be rationally organised, i.e., centrally planned. To totalitarians, markets always mean chaos, selfishness, sacrificing the public good for private gain. There is not one single instance of free marketeers overthrowing a democracy. However, history is replete with examples of socialists who dedicated themselves to that very goal. Maybe Cox and Co will give us examples of free marketeers who also committed themselves to the same miserable and destructive goal.