The threat to target the General, who took up his new job just nine days ago, was one of the real reasons that Labour MP Eric Joyce resigned as an aide to Defence Secretary Bob Ainsworth last week.
Former soldier Mr Joyce has told friends he attended a meeting at the Ministry of Defence where a discussion took place on how to target Sir David’s predecessor, General Sir Richard Dannatt, for criticising the Government’s failure to give enough support to British troops.
And The Mail on Sunday has established that Mr Joyce was also disturbed to hear Labour colleagues discuss Sir David’s 25-year-old daughter, Joanna Richards, who recently became Mr Cameron’s diary secretary.
Well-placed sources say Mr Joyce feared Labour was preparing to deploy more smear tactics against General Richards if he stepped out of line like General Dannatt.
‘He heard talk of Richards’ daughter working for the Tories and did not like it,’ said one source.