PACK up your clichés in your old kit bag and smile boys, smile.

Yes, we’re on the Western Front with Joan Littlewood safely ensconced in her literary chateau while we poor bloody infantry cower in our trenches in the stalls waiting for the verbal barrage to lift.

The irony of Littlewood’s finger-wagging condemnation of war is that although the crude propaganda doesn’t travel well, the vibrancy of the music most certainly does.

The writer’s premise is that the First World War was capitalism’s quarrel in which the snorting, grinning upper classes sent the stoical working classes to their deaths.

Nothing to do with the imperial ambitions of an expansionist, militarised industrial state, then.

Yet barely 30 years after this piece was written it was to be a left-of-centre political party that would start an illegal and genocidal war, for which we are still paying.

In the opening scene, one of the cast bizarrely and tastelessly gives the Hitler ‘sieg heil’ salute to a blown-up picture of Nigel Farage.

Perhaps Tony Blair could tell us precisely how many wars the UKIP leader has started?

However, if we put all this to one side, and mentally separate the clumsy dogma from the production, this is indeed a very fine piece of musical theatre.

Terry Johnson’s keenly observed direction is perfectly complemented by Mike Dixon’s music and designer Lez Brotherston’s bleak panoramas of the devastated France and Flanders. We feel the pain.

The British Army of 1914-18 marched not so much on its stomachs rather its vocal chords. Song after song reminds us of the fabulous lyrical anarchy of men facing death who were never found wanting in both courage and seemingly endless gallows humour.

Our guides through No Man’s Land are Wendi Peters and Ian Reddington who between them enliven some truly wonderful sequences, from the former’s natural feel for Music Hall to the latter’s hilarious comic pastiche as the mumbo-jumbo spouting recruiting sergeant.

Therein reside the contradictions of Oh What a Lovely War. For lurking beneath the tired stereotypes, so relentlessly milked by later writers such as Ben Elton, there lies a basic truth.

And that is the fact that while the political hues of our leaders may change, their attitudes to the led most certainly do not. Runs until Saturday, February 21.

John Phillpott