Communist after military intelligence, getting bogged down (5)
I believe the answer is:
mired
'bogged down' is the definition.
('mire' can be a synonym of 'bog down')
'communist after military intelligence' is the wordplay.
'communist' becomes 'red' (red is a kind of communist).
'after' says to put letters next to each other.
'military intelligence' becomes 'mi' (as in MI5 or MI6 - British military intelligence).
'red' after 'mi' is 'MIRED'.
'getting' acts as a link.
(Other definitions for mired that I've seen before include "Stuck in the mud" , "Sunk in deep mud" , "covered in muck" , "Bogged down" .)