Bar limits changes leading to group loyalty (9)
I believe the answer is:
tribalism
'group loyalty' is the definition.
(I've seen this before)
'bar limits changes' is the wordplay.
'changes' indicates anagramming the letters.
'bar'+'limits'='barlimits'
'barlimits' anagrammed gives 'TRIBALISM'.
'leading to' acts as a link.
(Other definitions for tribalism that I've seen before include "clan system" , "divisive tendency" , "ethnic customs" , "Strong group loyalty" , "Clannishness" .)