The chapter ends on two sentences that have nothing obvious to do with each other or with what precedes them. Fish should not be taken out of the deep. The sharp instruments of a state should not be shown to anyone.
The fish line reads as a proverb, and it works in two directions. A fish is safe while it stays where it cannot be reached, so it is advice about staying hidden. A fish out of water dies, so it is also a statement that a thing removed from its element loses whatever made it formidable. Both senses are live and the chapter does not choose.
The second line is unambiguous and is the reason this chapter is read as statecraft. The phrase rendered sharp instruments covers the effective apparatus of a government, its weapons and also its means of reward and punishment, and the instruction is that these should not be displayed. Deterrence by visible force is being rejected in favour of capability nobody has measured.
Between them the two sentences supply the practical content of the opening four lines. What the soft and weak overcome is not the hard and strong in general; it is the hard and strong that have been drawn out and shown. Chapter thirty makes the same point about armies, chapter fifty-eight about government that is searching rather than dull, and chapter seventy-two about a ruler who displays himself.
It is also a fair illustration of how the chapters are assembled. Two proverbs, a four-line pattern and a single named term are set side by side with the connections left for the reader, and different readers have drawn them differently for two thousand years.