Using leverage to infiltrate American rebellions (9)
I believe the answer is:
uprisings
'rebellions' is the definition.
('uprising' can be a synonym of 'rebellion')
'using leverage to infiltrate american' is the wordplay.
'using leverage' becomes 'prising' (I can't explain this - if you can you should believe this answer much more).
'to infiltrate' means one lot of letters goes inside another.
'american' becomes 'US' (United States).
'prising' put inside 'us' is 'UPRISINGS'.
Can you help me to learn more?
(Other definitions for uprisings that I've seen before include "Rebellions or mutinies" , "Revolts" , "Rebellious moves" .)