Has Not vs Cannot

Ah Leah
Here we go again
Ah Leah
Is it ever gonna end?
Ah Leah 
Here we go again
Ah Leah
We ain't learned our lesson yet
--Donnie Iris

Good point made by Prof Bylund. Stating that socialism has not worked is technically correct, but it implies that it could possibly work using some configuration that has yet to be tried. This is, of course, precisely what proponents of socialism suggest.

It's not an error to say that #socialism, or non-market planning and allocation of resources, has not worked historically, but it reinforces the illusion of it being a fixable problem. The fact is that socialism *cannot* work, which means it never will. #calculationproblem #Mises

— Per Bylund (@PerBylund) January 23, 2019

The more accurate statement is that socialism cannot work--a conclusion presented by Mises many years ago after careful analysis.