During the military junta years in Greece, he actively opposed the dictatorship and suffered permanent damage as the result of torture, making him a symbol of the anti-junta resistance.

Following the end of the war, Moustaklis, alongside other ex-EDES members, was enrolled in the Hellenic Military Academy.

[4] During a torture session he suffered brain trauma after a violent blow to his carotid artery and was subsequently rushed to hospital in a vegetative state.

[5] Despite that, years after the restoration of democracy, when asked during a documentary if he broke during interrogation, he was able to move his hands, in an animated fashion,[4] to indicate that he did not.

[4] Posthumously, the Greek State dedicated a memorial to him as recognition of his contribution to the struggle for democracy in Greece.

[8] He was awarded the honorary rank of Lieutenant General, and his name was given to the military camp housing the Recruit Training Centre of his home town of Missolonghi.