In a strongly-worded newspaper column that will be seen as a manifesto for turning the national team around before next year's World Cup finals, Postecoglou said a whole new approach was required both inside and outside the squad.
Successive 6-0 defeats in friendlies against Brazil and France resulted in German Holger Osieck being summarily dismissed as coach in Paris last weekend and prompted a wave of soul-searching in the local media.
"The fallout from two heavy defeats and national coach Holger Osieck losing his job has ignited some desperately needed and long overdue passion inside and outside the camp," Postecoglou wrote in Friday's Sydney Morning Herald
"The reason we are in this position is that we have lost sight of what our national team represents and what its role in our game is," the 48-year-old added.
"I have always believed that language is a very powerful tool and for a long time the language that we hear about the Socceroos has methodically stripped away any form of honour and prestige that a national team should represent.
"First and foremost the team belongs to the country itself and its fans. It does not belong to any coach, player or administrator. Any representation within the team and management should be seen as privilege not a right.
"For a long time the Socceroos have stood for courage and competitive nature in the face of adversity.
"But sadly this is no longer the case. What has happened over the past six or seven years is that self-interest, self-preservation and survival mechanisms have ensured that we no longer see ourselves as true Australian sportsmen.
"I have found it frustrating and infuriating to continually hear that we are not that good. That our expectations are too high. That we can't compete with the big countries.
"The sporting public don't want to hear that we must accept our fate. The national team is there to sell hope, not to dampen dreams."
Postecoglou, the coach of A-League side Melbourne Victory, firmed as the favourite to succeed Osieck on Thursday when he said Football Federation Australia (FFA) had approached his club about his availability.
FFA chairman Frank Lowy said on Tuesday that an Australian would be appointed to the job and that Postecoglou was one of three candidates with Graham Arnold and Tony Popovic.