It was an extraordinary gathering at the National Theatre yesterday, unprecedented in recent history: a roomful of two dozen artistic and executive directors convened from a regional theatre threatened with the cuts and hosted by Nicholas Hytner and Danny Boyle.

Why Danny Boyle? Because of the Olympic Games feel-good factor that still lingers after his brilliant masterminding of the opening and closing ceremonies, which can still serve as a flash point of everything that's good about our (lower case) national theatre, our entrepreneurial spirit, our creative resourcefulness and our health service.

In his youth, Danny was an usher at the Bolton Octagon. Today's Bolton Octagon artistic director, David Thacker, who has done serious time at the RSC and as Arthur Miller's greatest contemporary apologist (he even likes the bad plays, ie anything Miller wrote after 1965) at the Young Vic, weighed in with some passionate scare-mongering (the town is facing £95m in cuts over the next few years), while Tom Morris of the Bristol Old Vic wanted  us all to "out" David Cameron as a supporter of the arts; the PM loved and boasted of what the Olympics ceremonies had shown, why not extend the practical boastfulness to the network of artists and companies who made it possible?

We heard from Gemma Bodinetz of the Liverpool Everyman and Playhouse, Erica Whyman en route to the RSC from  Northern Stage,  Newcastle, Daniel Evans (a most accomplished speech) from Sheffield Theatres and Gareth Machin of the Salisbury Playhouse, who said he was fortunate in that his local government grant was at a four-year standstill; his friendly small-scale theatre contributes £10m a year to the local economy.

There was general amazement expressed that politicians still didn't get the economic argument. Hytner pointed out, almost as a postscript, that just 0.1 per cent of our total public spend goes on the arts. It's absolutely nothing at all in the greater scheme of things, and philanthropy only kicks in by following or matching public money; so the cuts will affect that, too.

The most depressing news was that the Birmingham Rep, with a major new refurbishment and rebuild alongside the new National Library in our second city, will open next year like a severely wounded animal, having lost £350,000 in core funding from a city having to administer 30 per cent cuts overall. Artistic director Roxana Silbert said that the 900-seater main auditorium will have to operate a "commercial" programme while the  purpose-built state-of-the-art 300-seater studio theatre probably won't open at all. That's more than a shame. It's a national disgrace.

Our cultural life is a patchwork of interconnecting events and improbable fictions. Danny Boyle said that he got the idea of alternating Benedict Cumberbatch and Jonny Lee Miller in Frankenstein at the NT from seeing the RSC alternating Richard II and Buckingham in Stratford-upon-Avon.

Daniel Evans said his life changed when he saw Ian McKellen's Richard III three times on tour in Cardiff. David Martin of the Oldham Coliseum said that there was only one entertainment alternative to his theatre in the town: heavy drinking. And Bodinetz recounted how her back-stage staff had  fitted up a boys' football pitch with new lighting and  reaped a technical skill spin-off from participation in the community.

None of this was hysterical or special pleading. It was the plain truth of the matter: that all of our lives are immeasurably enhanced and improved by state-subsidised theatres throughout the country which in turn contribute to the economy and perpetuate the not wholly ridiculous idea that our theatre - our actors and writers - are the best in the world.

And Max Roberts of Live Theatre, Newcastle, sounded a warning note in the light of our current obsession with "posh" actors who went to Eton - Damien Lewis, Eddie Redmayne, Dominic West and so on. Many young performers are discouraged by tuition fees and scarcity of grant aid, he said.

Like any garden landscape, our theatre needs constant revitalisation at the grass roots and the way things are going we could be denied the next generation of Albert Finneys and Glenda Jacksons.

The meeting, on the third floor "deck" level of the NT broke up in a pleasant mingling of directors and journalists, Boyle and Hytner splintering off to be interviewed by television crews and others such as Giles Croft of the Nottingham Playhouse more urgently distributing their latest publicity brochures.

In the case of Nottingham, their spring programme does rather look like a case of hoping to survive rather than forging ahead: a co-production with Salisbury of an old Alan Ayckbourn; a co-production with Birmingham Rep and the Ipswich New Wolsey of Philip Pulman's I Was a Rat! (one day the back catalogue of Pulman and Michael Morpurgo will be exhausted; then what?); and a stage adaptation, co-produced with the Liverpool theatres, of The Kite Runner.

Let's hope at least that there are one or two new Danny Boyles tearing the tickets in the aisles.