.TH Command HARDEN
.SY "harden <PLANES|SECTORS> <LEVEL>"
The \*Qharden\*U command is used both to install missiles
into protective silos which can prevent their destruction
during a nuclear or non-nuclear attack, and also to initially
construct and later reinforce military bunkers.
Each successive \*Qharden\*U command will add to the current 
hardness level of the missile or bunker in question.
.s3
Each point of hardening uses one unit of heavy construction materials,
and costs $5.  For bunker reinforcement, each point additionally 
requires 1 available worker.
.s3
Once a missile has been placed in a silo
(hardened to a level greater than 0)
it can no longer be moved.
.s3
See also : launch, nuke-types, plane-types, bunkers
