Can’t hope to change something in Whitehall (8)

I believe the answer is:

cenotaph

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'something in whitehall' is the definition.
I can't tell whether this defines the answer.

'can't hope to change' is the wordplay.
'to change' indicates an anagram.
'cant'+'hope'='canthope'
'canthope' is an anagram of 'CENOTAPH'.

Can you help me to learn more?

(Other definitions for cenotaph that I've seen before include "What divides Whitehall" , "Monument honouring persons buried elsewhere" , "Whitehall monument" , "Monument to those killed in war" , "Monument honouring the fallen" .)

I've seen this clue in The Times.

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