Cryptic crossword clue
Party leader built up a fabrication to provide security 3,2,4

The most common and most likely answer to this crossword clue is the 3 plus 2 plus 4 letter word PUT UP BAIL

I've seen this crossword clue in The Guardian
P
U
T
U
P
B
A
I
L

Buddy explains!

The straight part
We know that "provide security" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case provide security = put up bail.
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.

Latest crossword clues with full explanations