If anyone tries to diminish or destroy the BBC, I'll be manning the ramparts to defend it

I was 18 when I discovered the BBC World Service. Of course, Listen with Mother, Children's Hour, and Uncle Mac, had already long previously introduced me to the BBC Home Service. But the World Service was to prove a positive lifeline.

My discovery was rooted in Uganda. Never having been on a plane, never having even been out of England, I found myself in 1967 on the banks of the Nile in a little, two-room shack on the edge of Kamuli College in a small village called Namasagali. Bereft of phones and radio communications, I was some 15 miles on a mud road from the nearest post office.

The traumatic shock of being propelled from the shelter of my Yorkshire home to this green and distant place, 150 miles from Kampala, was more than I could bear. But on my second homesick, tearful night, the headmaster, Father Grimes, gave me an old valve radio with 10 bands of shortwave. So began my true love affair with the BBC. The news, the variety, the voices, the constant interference, combined to weave this link to all that I had known before, and remained so for the year that I was there.

These days, I depend as strongly as ever on a much bigger BBC than ever existed then. But the World Service remains in my soul – visited on late nights and early mornings when home. When abroad I refer to it constantly, and nowadays, far from valves, I consume it online. In these days, too, I worry about the starvation of the World Service, the failure of government to recognise it as the stunning, envied manifestation of the UK's "soft power". The decisions to squeeze the corporation, and to fail to invest in it, flow from the decision of government no longer to fund it directly. It leaves me increasingly convinced that such a decision can only have been taken by politicians who have never been anywhere – particularly in the developing world.

For the rest, I am a Radio 4 addict. Whisper it softly, but from my own non-BBC roots at LBC (the first legal, commercial radio station ever to broadcast in the UK), I have been convinced that radio is the ultimate medium – not least because the pictures are so much better. The stimulation of all the senses by radio is unique. The BBC's deployment of the medium is without parallel anywhere in the world. In the car, at home, at my desk, on my phone, Radio 4 is in and out of my life every day that I am in the UK. Abroad, it is increasingly with me online.

Mentioning online, the BBC has few, if any, challengers.

As a choral scholar at Winchester Cathedral who sang Bach and Tallis at eight, Radio 3 rattles and succours my bones. From Handel to Howells, from Fauré to Finzi, it cushions my news and current affairs and brings solace whenever I need it.

The quality of the BBC's television output remains world beating. In short, the creation and maintenance of the BBC as the greatest broadcaster in the world goes to the very core of what the word "British" means.

So why have I never worked for this great national and global asset that I depend upon and admire so much? Well, it's a hard question to answer. In part, it's because I am somewhat non-conformist. In part, beyond a tentative approach quarter of a century ago, I have never been asked. I like the freedoms offered by the other public broadcaster, Channel 4. It was established to be different. I guess I feel myself, though in part deeply conventional, also to be different. But make no mistake, if anyone ever tries to diminish or destroy the BBC, they will have to contend with a myriad of people who, like me, will be manning the ramparts to defend it.

I am delighted that my former boss Richard Tait and my good friend John Mair have decided to compile a book about the corporation's future. Though whether they will approve of my introduction as true BBC hands themselves, I can't say.

This is an edited version of Jon Snow's introduction to 'The BBC Today: Future Uncertain' (Abramis). Edited by John Mair, Professor Richard Tait and Professor

Richard Lance Keeble, the book will be published later this year