All 3 Uses of

fortify
in
The Killer Angels

Eariy said slowly, "To move this entire Corps, in the face of a fortified enemy?"†
Chpt 1.6 *

The generals of Europe are still ordering massed assaults against fortified positions long years after his death, in 1904, at the age of eighty-three.†
Chpt Aft.

Definition:

to make stronger

in various senses, including:

to add defensive fortifications to a site to withstand attack -- as in "fortify the camp"
to make a structure or organization stronger -- as in "fortify the wall"
to inspire emotional and mental strength -- as in "fortify her spirits"
to strengthen an argument -- as in "fortify our argument"
to add nutrients to increase the healthfulness -- as in "bread fortified with folic acid and iron"
to add alcohol to make a drink stronger and/or less prone to spoiling -- as in "port, sherry, madeira, and other fortified wines"