Interdiscursivity has close affinity to recontextualisation because interdiscourse often implies that elements are imported from another discourse.
illustrates the three levels: A minister of environment speaks in the parliament about a proposal.
The example illustrates that 2. and 3. are specific cases of 1, in the sense a-c all relate to another discourse.
This is explained in Marc Angenot and Bruce by reference to Bakhtin: In Bakhtin's dialogism, the utterance is the natural meaningful and finalised unit of speech, which others are supposed to respond to, that is, others interpret the utterance by situating it in a discursive context.
Since interdiscourse privileges certain interpretations, it has a close affinity to the concepts of ideology, hegemony and power (sociology).