Bad military command makes you nervous (3,2,4)
I believe the answer is:
ill at ease
'nervous' is the definition.
(I've seen this before)
'bad military command' is the wordplay.
'bad' becomes 'ill' (associated in meaning).
'military command' becomes 'at ease' (I've seen this in another clue).
'ill'+'atease'='ILL-AT-EASE'
'makes you' is the link.
(Other definitions for ill at ease that I've seen before include "awkward" , "discomfited" , "Nervous, uncomfortable" , "wound up" , "Uncomfortable with a situation" .)