On the day Mrs Thatcher died, I caught up with Dominic Cooke's farewell production as artistic director of the Royal Court. The narrator in Bruce Norris's The Low Road is none other than Adam Smith, the 18th-century moral philosopher and economic theorist whose book, Wealth of Nations, Mrs Thatcher is said to have carried in her handbag at all times, symbolically at least.

In a disappointing dog's dinner of a production, Cooke and Norris seem to be having their cake and eating it, as befits a theatre that has, since Stephen Daldry's regime, enthusiastically embraced the mixed economy in the arts and learned to adjust to post-Thatcherite realities of bolstering public subsidy with private sponsorship.    

So, the Low Road hero is an entrepreneurial bastard son of George Washington (possibly) - played in a hectic gabble by Johnny Flynn - who prospers in the sex and slave trades of Masssachusetts before falling victim to his own principles of self-interest and self-help. The epic ambitions of the piece are admirable, and some of the picaresque episodes fairly entertaining, but there's no clarity or focus to the show, which is overburdened with ugly design and bedevilled by some of the worst acting seen on this stage for years.

There's even a ludicrous spaceship at the end, descending dramatically for the convenience of a couple of children's theatre aliens to inform us that capitalism, and the world, is doomed. This only compounds the triteness of the "surprise" second act opening scene which comes starkly up to date at a contemporary economics forum that is disrupted by slogan-chanting protesters.

There's nothing to compare here with Caryl Churchill's two great Thatcher responses of the 1980s, Top Girls and Serious Money, the first of which resonated poetically and theatrically with ideas of feminism and womanhood in public and private life, the second prophetically analysing the greed is good culture in the City that has resulted in our catastrophic financial crisis and climate.

It's hard to see in Norris' play how his parable justifies his conclusions, whatever they are, nor is it very clear where Adam Smith himself, played with a twinkling but always ambiguous (and mysteriously microphoned) objectivity by Bill Paterson, stands on his own story. But it's certainly easier to side with the Adam Smith view of the world than it is with the satirical intentions of the Royal Court: that there can only be benefits for all if wealth is generated by the swashbuckling few.

Acknowledging the irony of their own position in such a state of affairs, the Court and Bruce Norris give Adam Smith a sly, rather smug, little aside about the contribution of the theatre's patrons. It's a palpable legacy of Thatcher, this gnawing sense of unease about private money in public theatres, and one lately addressed head on at the National Theatre in its "get the sponsor" productions of Timon of Athens and Scenes from an Execution.

It will be intriguing to know how audiences at The Audience and Billy Elliot adjust to the demise of the former Prime Minister; in the first, Haydn Gwynne presents a ferocious, bustling version of Thatcher impervious to criticism (even from the Queen) of her foreign policy in South Africa, while the second evokes a Spitting Image blow-up of the Iron Lady in the background of a boisterous, old-fashioned agitprop sketch about industrial unrest.

The really great thing about Mrs Thatcher, of course, was that she simplified political argument in the gale force of her own convictions, so that you really did find out what you yourself thought about things. And New Labour came about as a pale copy of Thatcherism because the diehard Labour Party working-class vote (excluding the peripheral extremists) woke up one morning and discovered that they agreed with her after all.

Predictably enough, Michael Billington reiterates this morning in The Guardian the old mantra that Thatcher seized on Andrew Lloyd Webber as a "symbol of what theatre should be" - and she certainly used him as a stick to beat a beleaguered Peter Hall with at one point. But Thatcher didn't really know or care about what theatre should be; she responded merely to the branding and globalisation of the product. As Mark Lawson said in the mid-1990s, "every one-horse town in the world now has Coca-Cola, McDonald's, CNN and a Lloyd Webber show." 

That kind of comment crept increasingly into criticism, which assumed a blandness in Lloyd Webber's work where, in fact, no blandness existed. For the theatre, or the subsidised wing of it, he became another puppet in the Thatcher gallery of villains. But the myth took hold, and so did the Thatcherite idea that, as Billington says, a popular musical could be a passport to success in the "serious" theatre.

And the "serious" theatre itself got round that awkward one by claiming, probably correctly, that good musical theatre was as serious as "serious" theatre anyway. Mrs Thatcher couldn't have cared less, probably, about Richard Eyre producing the David Hare trilogy at the National (the best thing he ever did), but she would have loved the fact that he also directed Mary Poppins in the West End and on Broadway.      

Interestingly, I didn't really get a sense at the Royal Court last night that the audience was making any connection at all with the Thatcher legacy. I was more struck by the fact that Dominic Cooke has bookended his highly successful Royal Court regime with plays by an American author who is much better at lacerating his own country's history of racism, sexism, bigotry and domestic hypocrisy than he is at building an arc of historical and political epic appropriate or meaningful to London audiences.

But the attempt is to be applauded. And perhaps they were applauding it in the Downstairs bar last night where Cooke was being given his send-off by colleagues and supporters, thereby depriving a packed house of punters any access to the bar before the show. That in itself became a metaphor of power to the few so the masses may benefit!

If nothing else, The Low Road offers signs, but no shortcuts, to the sort of play that might really wrestle Thatcher to the ground. For as more than one commentator has pointed out, the country we live in is, by and large, for good and mostly for bad, the one she created.