Former director general of the BBC Greg Dyke says the Corporation is the envy of the world – yet faces an uncertain future because of "hostile politicians".
He said the broadcaster moreover faced opposition from commercial interests & parts of the press, who are out to "destroy it for their own financial reasons".
And he warned that Britain would be a "much poorer place without the BBC".
Speaking at a discussion approximately the future of the BBC held at the British Academy in central London, Mr Dyke argued that the Corporation plays a crucial role in British life.
He said: "Go around the world & talk approximately the BBC & in so many countries people are in awe of it. It is one of the world's tremendous brands."
He said that as chairman of the FA, he turned to the BBC to reinvigorate the fledgling FA Cup football tournament.
He said: "We used their brand, their integrity, their marketing power to assist rebuild the FA Cup.
"The result after one season was brilliant.
"And yet we have politicians who don't understand the BBC, what it has achieved, & want to see it diminished largely for political reasons."
He accused some politicians of wanting to undermine the BBC because it challenges their view of the world.
He said: "Those successes at the BBC over so many years undermines their fundamental belief that there is only one way of organising society.
"My greatest fear is that one day they will win, & we will wake up & discover that the BBC has gone, & it's only then that we understand what it delivered.
"There is no other country in the world who would even have this debate."
He moreover singled out the BBC's biggest rival, ITV, for criticism. ITV has accused the BBC of breaking promises that it would not chase ratings.
Mr Dyke said: "ITV should be ashamed of their current position."
"ITV today is just being commercially opportunistic," he added.
The future of the BBC is up for discussion as part of the charter review.
Musician Brian Eno moreover spoke up for the BBC & lashed out at commercial TV – which he said he "hates".
Although he admitted he has not owned a television since the early 1980s.
The former Roxy Music member, who was one of a panel of four discussing the BBC's future, said he wants broadcasting to become "more elitist".
He told the meeting: "I should confess at this point that I don't even have a television, & I haven't had one since the early 1980s, because actually what I love is radio & in fact I love BBC radio so much I frequently write to them like some mad fan."
He said TV should become more like radio & play to people's niche interests.
He said: "My vision for the future of television is to be more like radio. I find radio much more serious, much more engaging & much less entertaining.
"I'm bloody sick of being entertained.
"I don't want to be entertained, I want to be provoked, I want something to think about. And between Radio 4, the World Service & Radio 6, there is a lot to think about.
"I want to make television, I suppose, even more elitist really. Even more catering to niche people like me."
And he took a swipe at commercial broadcasters, which he said he "can't bear", & warned against privatising parts of the BBC & leaving a rump.
He said: "It'll turn out that all the satisfactory bits of the BBC, all the bits we want, will disappear or obtain hived off because they are profitable, & then obtain turned into c**p.
"I suppose I don't have a television because I so hate commercial television. I can't bear it. It depresses me & it makes me want to shoot myself to think people spend their lives making this stuff."