Nephites successful against the Gadiantons

3 Nephi 3 20-21
20 Now the people said unto Gidgiddoni: Pray unto the Lord, and let
us go up upon the mountains and into the wilderness, that we may fall
upon the robbers and destroy them in their own lands.
21 But Gidgiddoni saith unto them: The Lord forbid; for if we should
go up against them the Lord would deliver us into their hands;
therefore we will prepare ourselves in the center of our lands, and we
will gather all our armies together, and we will not go against them,
but we will wait till they shall come against us; therefore as the
Lord liveth, if we do this he will deliver them into our hands.

When the Nephites were righteous they chose righteous and inspired
leaders. Gidgiddoni was such a man. He led the Nephites against the
Gadianton robbers. The Nephites were successful because they fought
the Gadianton's in their home territory, rather than attacking the
Gadiantons in their lands. Rather than taking preemptive action, they
prepared and fought defensively and were successful.