Look to imprison a revolutionary in Texas city (6)
I believe the answer is:
laredo
'texas city' is the definition.
(I've seen this in another clue)
'look to imprison a revolutionary' is the wordplay.
'look' becomes 'lo' (archaic exclamation meaning 'look!').
'to imprison' indicates putting letters inside.
'revolutionary' becomes 'red' (red can informally mean communist).
'a'+'red'='ared'
'lo' enclosing 'ared' is 'LAREDO'.
'in' acts as a link.
(Other definitions for laredo that I've seen before include "US-Mexico border town" , "Texan city" , "US city" .)