The Big Smoke

Like many teenage boys, I was fascinated by World War II. I collected Airfix models, was obsessed with anything produced by Pat Reid, especially the 'Escape From Colditz ' board game, and believed Sven Hassel to be the greatest writer of the twentieth century. Then one day we were asked to bring our favourite book to school to discuss in English; I brought my latest Hassel, the cover of which would almost certainly have featured some combination of a bloodied German corpse, thrusting Panzer, demolished houses, fire, Swastikas and, of course, Hassel's name, picked out in embossed gold and with the double 's' made to look like the SS logo.

Classy.

Unfortunately, this was also the day on which the German exchange students came to school. I was asked to look after one, which meant taking him to English. Suddenly, my choice of reading matter didn't look quite so big or clever. He looked at me with sad eyes, his face reflecting a historical burden that I, as victor and without the scars of Nazism to bear, had never previously understood. 'Why do you read,' he said, his voice rich with disappointment, 'books like this.'

I had no answer. And war never seemed quite so much fun again.

But despite all that, I love the Imperial War Museum. And that's partly because it has put on some of the best temporary exhibitions I have seen in London – Great Escapes, Weapons of Mass Communication and last year's stunning In Memoriam, about the First World War. So I was expecting great things from Outbreak, their latest exhibition about the mood in Britain in September 1939, as the nation prepared for war.

At the same time, the IWM's other London outpost, the Cabinet War Rooms, is also putting on a temporary exhibition – its first. Undercover also looks at the mood of the nation on the outbreak of war, but does so specifically with regard to the Cabinet War Rooms, which were already completed and awaiting occupation. The exhibition feature objects from the War Rooms and quotes from the personnel who worked there, building a fascinating picture of what life must have been like in this secret underground warren, where everything revolved around the extraordinary figure of Winston Churchill. A transcript of a Churchill speech, with handwritten amendments, is one of the key exhibits but in general this is a classic exhibition of the IWM type, using small personal objects to tell huge and important stories.

After the war, the Cabinet War Rooms were mothballed, visitable only be special arrangement until 1984, when Michael Heseltine, then Secretary of State for Defence, wrote to Margaret Thatcher to suggest they were opened to the public – a letter that concludes a clever exhibition, which ultimately gives you the story of the War Rooms in their entirety.

If you have never previously visited this attraction, this is the ideal time to do so.

The exhibition works because it only has to cover the Cabinet War Rooms, whereas the Imperial War Museum's Outbreak is trying to capture the tone of an entire nation. There are some splendid items – particularly some of the propaganda books produced to justify the war from both sides – but also a sense that the curators are trying to do a little too much. Displays telling intimate stories from the home front (the first war wedding; the first war babies) share space with hard facts about war preparation (gas masks, ID cards, blackouts), all featured alongside the bigger-picture activities of soldiers, politicians, journalists and royalty. There is some lovely stuff, but it doesn't quite hang together as successfully as the display at the Cabinet War Rooms. The IWM has been outdone, then, but at least it's keeping it in the family.