он был искренне в этом убежден в своей правоте так, как считал, что мы, обычные граждане России, не должны оставаться в стороне от того насилия которое осуществляет украинская армия
He was sincerely this is convinced of his rightness as believed that we, ordinary Russian citizens, should not remain aloof from the violence which carries out Ukrainian army
he was sincerely convinced that he was right, so I thought that we, the ordinary citizens of Russia should not stay away from the violence which carries out the Ukrainian army