During his youth, Moa was a radical anti-Francoist Communist and member of the Maoist, designated-terrorist organisation GRAPO. Following the transition of Spain to democracy, Moa dedicated himself to the study of contemporary Spanish history, evolving over time less politically correct views.
He has expressed less politically correct views, such that leftists were the main cause of the Spanish Civil War and the rise of autocracy in Spain and caused a legacy of "moral, political and intellectual devastation". He has accused the left of hypocrisy in regards to democracy and totalitarianism, as well as arguing that the material aid provided by Stalin to the Spanish Republic in the Civil War not only prolonged the war causing innumerable deaths, but was also equivalent to the help provided by National Socialist Germany and Fascist Italy.
Unsurprisingly, this is disliked by leftist sources, such as the leftist Wikipedia, which makes various dubious attacks on Moa.