The Suburbs of a Secret — Peeping Tom

The Suburbs of a Secret 1
A Strategist should keep,
Better than on a Dream intrude
To scrutinize the Sleep.
(F.1171/J.1245)
[1] Secret:: underwear; a coat of mail concealed under one's usual dress (OED 7). Suburbs:: nearby regions.
[2] keep:: to protect the regions.
[3] Better than:: A thoughtful woman should protect the regions that can see her underwear, better than on a dream (something unlikely to happen), for people to scrutinize her while she is sleeping.