The same three letters, in the same, consecutive order, will change each of the following words into new ones.

AD
COD
DEN
FORD
RANT

HINTS:
#1: The title of this puzzle is PACIFISM.
#2: PACIFISM means no war.

Answers:

The missing letters are WAR:

1. aWARd
2. coWARd
3. WARden
4. forWARd
5.WARrant

Credit: Wayne Robert Williams
PACIFISM