Nuestro Amigo El Che
Here are two articles on the subject of Che Guevara. One an account of the evolution of Che's image as captured by Korda from the BBC and another an historical account of Che's role as an executioner from Libres.org [machine translation]. The question "who was Che" is probably better framed as "how has he been marketed?" As the BBC story notes the Korda image of Che has become an "anti-war" poster; an environmental poster, a logo for ice cream and a t-shirt graphic to boost coca leaf sales. Anything except the executioner.
It is probable that the real Che Guevara was hard-hearted, dedicated Bolshevik. An executioner. That's what Bolsheviks were in those days. It came with the job. But we prefer not to remember Che that way. As the quote from the movie "Who Shot Liberty Valance?" says "if you are forced to print the truth or the myth, you always print the myth."