US shooter Jack disrupted nation (9)
I believe the answer is:
tarantino
'us shooter' is the definition.
I don't know anything about this answer so I cannot judge whether it can be defined by this definition.
'jack disrupted nation' is the wordplay.
'jack' becomes 'tar' (both are informal terms for sailor).
'disrupted' is an anagram indicator.
'nation' anagrammed gives 'antino'.
'tar'+'antino'='TARANTINO'
Can you help me to learn more?
(Other definitions for tarantino that I've seen before include "He makes films" , "Quentin -, American film director" , "Quentin -, US director" , "Quentin ... film maker" , "Who in tarnation is this US film-maker?" .)