Cruise with a warmonger's axe or missile (8)
I believe the answer is:
tomahawk
'axe or missile' is the definition.
(tomahawk can mean an axe or a cruise missile)
'cruise with a warmonger's' is the wordplay.
'cruise' becomes 'tom' (actor Tom Cruise).
'with' means one lot of letters go next to another.
'warmonger' becomes 'hawk' (hawk is a kind of warmonger).
'tom'+'a'+'hawk'='TOMAHAWK'
(Other definitions for tomahawk that I've seen before include "North American Indian hatchet" , "Scalping weapon" , "Native American fighting axe" , "its strike can be fatal" , "Native American war-axe" .)