Briefly endanger, with little hesitation, supreme power (8)

I believe the answer is:

imperium

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'supreme power' is the definition.
'imperium' can be an answer for 'power' (thesaurus). I'm not sure about the 'supreme' bit.

'briefly endanger with little hesitation' is the wordplay.
'briefly' means to remove the last letter.
'endanger' becomes 'imperil' (synonyms).
'with' says to put letters next to each other.
'little hesitation' becomes 'um'.
'imperil' with its last letter removed is 'imperi'.
'imperi'+'um'='IMPERIUM'

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I've seen this clue in The Times.

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