"To send men to the firing squad, judicial proof is unnecessary...These procedures are an archaic bourgeois detail. This is a revolution! And a revolutionary must become a cold killing machine motivated by pure hate. We must create the pedagogy of the The Wall! (El Paredón)" --Ernesto 'Che' Guevara
"Committed mass murder of political opponents" ought to cover it for most reasonable folk.
A good book that covers the thought of Che-boosters and their results is:
Guide to the Perfect Latin American Idiot
One of the few critical bios I found (but not read) is the following:
Exposing the Real Che Guevara: And the Useful Idiots Who Idolize Him
Alvaro Vargas Llosa had an essay in The New Republic (liberal, center-left political magazine) on the use of a communist mass-murderer as a capitalist tool:
The Killing Machine: Che Guevara, from Communist Firebrand to Capitalist Brand
It is customary for followers of a cult not to know the real life story of their hero, the historical truth...It is not surprising that Guevaras contemporary followers, his new post-communist admirers, also delude themselves by clinging to a mythexcept the young Argentines who have come up with an expression that rhymes perfectly in Spanish: Tengo una remera del Che y no sé por qué, or I have a Che T-shirt and I dont know why.