hiː ˈɑːɹɡjuːd ðˌɐɾɪt wʌzðɪ ˈɪnflʌks ʌv mˈɪdəlklˈæs ɹˈædɪkəlz ˌɪntʊ ðə lˈeɪbɚ pˈɑːɹɾi dˈʊɹɹɪŋ ðɪ ˌɪntɚwˈɔːɹ jˈɪɹz ðæt hæd tɹænsfˈɔːɹmd lˈeɪbɚ fɹʌm ɐ tɹˈeɪd jˈuːniən pɹˈɛʃɚ ɡɹˈuːp ˌɪntʊ ðə mˈeɪn pɹəɡɹˈɛsɪv pˈɑːɹɾi.
He argued that it was the influx of middle-class radicals into the Labour Party during the interwar years that had transformed Labour from a trade union pressure group into the main progressive party.