Military Intelligence inside give command (8)
I believe the answer is:
dominate
'command' is the definition.
(I know that command can be written as dominate)
'military intelligence inside give' is the wordplay.
'military intelligence' becomes 'MI' (as in MIt or MIe - British military intelligence).
'inside' indicates putting letters inside.
'give' becomes 'donate' (donating is a kind of giving).
'mi' put into 'donate' is 'DOMINATE'.
(Other definitions for dominate that I've seen before include "Govern" , "Master" , "Look down on; have control over" , "corner" , "Admit one in order to be in control" .)