For the American release, Listen to Britain opens with a foreword spoken by Leonard Brockington added by a "nervous civil servant" as there were fears that Americans may be confused by the ambiguity of the film's message. The forewords begins with the famous Listening to Britain poem:
Before the introduction was added, Edward Anstey in The Spectator thought the film would be a complete disaster. Writing in the Documentary News Letter, Anstey complained:
However, Anstey admitted that Listen To Britain "had enormous influence overseas" and the film went down very well with audiences. Helen de Mouilpied (later the wife of Denis Forman), the deputy head of non-theatrical distribution for the Ministry of Information, recalled:
Roger Manvell then working as the Films Officer in the South West and later North-West of the country, claimed he always tried to show the film as the:
The success of 'Listen To Britain' in influencing British public opinion vindicates Jennings and shows "boundary lines in the debate over social utility and aesthetic pleasure are not as distinct as they may seem."
Listen to Britain may be considered as artistic or poetic but the film is based on ambiguity and doubt. Mass Observation, co-founded by Humphrey Jennings in 1937, found in the war's early years that the public considered it “un-British to shove propaganda down your throat”, so Jennings realised that he would have to take a different approach to succeed. Jennings therefore chose to hide the propaganda with ambiguity. The film is therefore part of what Stuart Legg called the 'Poetic Line', in spite of Ansley and Anderson's beliefs that poetry and propaganda were incompatible, and the use of poetry in relation to the constraints imposed by the audience and motivations of Jennings and the Ministry of Information in making the film is central to understanding the film as a work of propaganda. "Poetry and propaganda come together in the myth of the people's war."
In Listen to Britain, Jennings is selling a myth of national unity; that in spite of pre-war differences all classes were united in war socialism but it's a bottom up view that highlights individuality, the "unity within difference". Having learnt through Mass Observation that the British people were uncomfortable with detecting propaganda, Jennings used a poetic style to mask it. The use of sound was vital in this, allowing the montage of shots to imply hidden meaning, such as the sound of an unseen aircraft on a seemingly peaceful day. Edgar Anstey feared the "beauty" would detract from the message and when the film was released in America, an introduction was added because the art had made the message ambiguous. Only at the end was the film's ambiguity dropped as Rule, Britannia! plays out over a sequence that at last implies 'totalised' unity. "Propaganda finally wins out over poetry".
A 'voice of God' narrator is absent but Jennings uses the vastly different sounds from people of different classes at home or in the work place as the voice of the people. These sounds, and especially the songs, help unite the viewer. Jennings conceals his own voice behind an impersonal style so the viewer can listen to the sounds of Britain. Jennings also goes further, using creative treatment and reconstruction to mislead the audience who may believe they are watching vérité. Leaving in the serendipitous stumbling child and Jennings’ obsessive technique, pointed out by Mike Leigh, of getting the actors to scratch their noses, adds to this sense. This non-perfected style contrasts markedly with more traditional, overt propaganda. While Jennings ignores many genuine problems, such as showing un-bombed homes or menus not ration cards, the use of sound without narration allowed Jennings to mask the propaganda as the meanings were not imposed on the viewer. This allowed the audience to make up their own mind from the images and the music alone, and this apparent freedom, along with the many, diverse voices, helps conceal the true nature of the message as Goeffrey Nowell Smith explains.
Jennings makes the tensions in the myth's construction central to the film. Britton believes the myth was created to benefit the elite's Imperial war, while Leach believes aspirations for future social change were integral to the war unity ideology. Jennings highlights class distinctions and hints at the tension between the forces for and resistant to social change. Accepting the myth's fragility, the scene with the music hall double act Flanagan and Allen performing to a working class audience cuts straight to the Queen enjoying the music of Myra Hess at one of the (London) National Gallery's lunch-time classical music concerts. Whether the classes are united with the Queen among her people or rich and poor are permanently divided is up to the viewer. Likewise gender; women are shown firmly within the family unit despite a sub-textual admission of future liberation aspirations. This ambiguity masks and therefore strengthens the propaganda.
In Mein Kampf, Hitler talks of the success of British propaganda in World War I believing people's ignorance meant simple repetition and an appeal to feelings over reason would suffice. In contrast, Jennings' "calm voice of reason appeals to the mind rather than emotion". In Triumph of the Will, for example, Leni Riefenstahl works with the myth and ignores the reality, while Jennings acknowledges their differences. A.J.P. Taylor believes Britain's war socialism represented genuine unity, allowing Jennings to admit these tensions given the public's distaste for overt propaganda. Thus for Jennings the poetry and propaganda "enrich and unsettle each other". This subtle reflection upon the myth “genuinely was propaganda as art, an extraordinary feat which Triumph of the Will doesn’t come near, thankfully”.
In 2012, the London-based band Public Service Broadcasting released Waltz for George which uses images taken from several Ministry of Information war films, though mostly from Listen to Britain, to accompany the radio report on the soldiers returning from Dunkirk. The same year, they also released London can take it with both audio and video taken exclusively from Jenning's 1940 propaganda documentary of the same name.