Nullified the need to possess a gun (7)
I believe the answer is:
negated
'nullified' is the definition.
(I've seen this in another clue)
'need to possess a gun' is the wordplay.
'to possess' indicates putting letters inside.
'a gun' becomes 'gat' (US informal term for a gun).
'need' going around 'gat' is 'NEGATED'.
'the' is the link.
(Other definitions for negated that I've seen before include "Abrogated" , "Discredited" , "Made ineffective" , "Cancelled or destroyed the effect of something" , "Nullified" .)