The most common and most likely answer to this crossword clue is the 14 letter word SABRE-RATTLING
I've seen this crossword clue in Financial Times
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Buddy explains!
The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does SABRE-RATTLING mean?
SABRE-RATTLING verb- To threaten a big battle or war.
- A flamboyant display of military power as an implied threat that it might be used.
- Any threat, such as one company threatening another with a lawsuit.
- Bellicose; threatening military action.