Sentence:  Seeing the British establishment struggle with the financial sector is like watching an alcoholic […]. Until 2008 there was denial over what finance had become. […] But the scandals kept coming, and so we entered stage three – what therapists call "bargaining". A broad <WSD>section</WSD> of the political class now recognises the need for change but remains unable to see the necessity of a fundamental overhaul. Instead it offers fixes and patches. 
Meaning of the word marked with <WSD> tags:  A part, piece, subdivision of anything.