Clue: Disgust over senior journalist on papers showing fanciful ambition (4,5)
Answer: PIPE DREAM
Explanation: Definition: fanciful ambition 
**PIP **(disgust?) + **ED** + **REAM **(papers) 
I've not been able to find DISGUST as a synonym for PIP, and I've checked three dictionaries and several online sources. The closes definition of PIP that I can find is "to annoy", but that's not the same as "to disgust".