Diplomacy was overwhelming, international leader implied (5)

I believe the answer is:

tacit

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'implied' is the definition.
(synonyms)

I cannot understand how the remainder of the clue works.

(Other definitions for tacit that I've seen before include "Wordless" , "Implied -- inferred" , "Understood without being directly expressed" , "Unspoken but implied" , "Not said though understood" .)

I've seen this clue in the Sydney Morning Herald.

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