First Night: The Power of Yes, Lyttelton, National Theatre

When its artistic director, Nicholas Hytner, decided last spring that the National Theatre needed to make a spirited response to the global recession, he did what any smart person in his position would have done. He picked up the phone and rang for David Hare. If there's an English dramatist who could be relied upon to offer a clear, combative analysis of this mind-knotting, epoch-making mess, it's the author of Stuff Happens and The Permanent Way.

Pessimists will have spotted a faint potential flaw here. If our pre-eminent political dramatist had been gagging for this important gig, he'd surely have been down the line to Hytner first. They will also have noted that share prices in the project took a tumble this summer with the advent of rogue trader, Lucy Prebble, author of the uber-hit Enron, a play which seems to have cornered the market in flamboyant prescience and in the ability to explain the fiendish con-tricks of creative accountancy with dazzling theatrical immediacy.

So where does leave The Power of Yes? Gazumped, bothered and bewildered? Not quite. But, in truth, it's looking a tad tardy and more than a mite dogged and dutiful, with all due allowance for the difference in genre and despite the succession of (rather listless) digital images that strive to give urgency to Angus Jackson's stubbornly tepid production. Subtitled "a dramatist seeks to understand the financial crisis", this piece is not so much a play proper as an artfully arranged dramatisation of the research that could have led to one.

Portrayed by Anthony Calf, the Author-figure (who is a version of Hare) takes to the stage and scribbles endlessly in a notebook, while quizzing a recurring crew of financiers, politicians and journalists. You feel that he must have been trapped for the past year in a bunker, such is the surprise he evinces when the men in suits (who include Adair Turner, the chairman of the Financial Services Authority, and George Soros, a US banker) march forward and bark at him what we largely already know.

Howard Davies, the first chairman of the FSA, keeps dragging in a blackboard on which he has chalked the acronym S-L-U-M-P (for sub-prime, liquidity, unravelling, meltdown, and pumping). It's supposed to suggest a quasi-Shakespearean five-act structure but it merely indicates the stolid, spelt-out-to-a fault manner in which The Power of Yes tells a momentous story that embraces the four days in September 2008 when capitalism came to a grinding halt. There's a great Samuel Beckett title, Imagination Dead Imagine. Subtitled "Capitalism Suspended Speculate", my dream Hare drama on this issue would view the crisis from the single vantage point of that vertiginous week in Washington during which America had to reinvent itself as a socialist country. The author of Stuff Happens, the best play written on the run-up to the Iraq war, might have been born to dramatise the heady deliberations of those days.

Instead, he's given us a sort of Everything You Wanted to Know About the Credit Crunch, But Were Afraid to Ask. It's honourable, lucid, tenacious, and a little dull. You want "securitisation" explained? Banker David Marsh has quite a good imagination for what happens when the originator and the holder of a loan get separated. It's like pain moving round in disguise: "You stub your toe but it's your elbow which hurts." But what we see is the weedy spectacle of businessmen swapping pages from their portfolios, an emblem that does not gain in power by being duplicated digitally overhead.

Even as journalism, the piece lacks dialectical edge. Hare's central contention is that the collapse of the financial system in 2008 makes this recession radically different in kind from its predecessors and that bankers are a priesthood who have a vested interest in warding off legislation by pretending that this is just a bust like any other. But the financiers to whom he talks are, by and large, rueful, reformed characters who eloquently agree. He'd toughen his case, if he had to slug it out with an unreconstructed swinging-dick Darwinian who might argue the financial innovations that were criminal in one era have often passed into respectability in the next.

The Power of Yes underlines the paradoxes of the crisis with characteristic incisiveness – the fact, say, the Communist China with its cheap goods and labour, helped to create the artificially flush conditions in the US that led to the sub-prime fiasco. Due scorn is poured on capitalism's fat cats who came yowling for a socialist bail-out. But sometimes it's through noticing the smaller ironies that the piece scores best. I liked the contribution from the deputy-director of a Citizens Advice Bureau whose job it is to counsel the impoverished on the order in which to pay their bills. You have to settle up your council tax or you face prison. But credit card companies are inclined to pass on the debt from one to another. No change there, then. "You could argue," he points out dryly, "that in the long run the system works in yoir favour".

That has real dramatic life. But when our author-figure starts proclaiming about the death of an idea (that markets are decent and wise) – look, he says, "It's lying dead on the stage," you may feel that it's not the only thing that's lying there in that condition.