Alma 48:14

Now the Nephites were taught to defend themselves against their enemies, even to the shedding of blood, if it were necessary; yea, and they were also taught never to give an offence; yea, and never to raise the sword, except it were against an enemy, except it were to preserve their lives:

The Nephites were taught to defend themselves from their enemies. They could kill if they had to. But they were also taught never to attack first. They were taught never to use the sword unless an enemy attacked them. They only fought to save their lives.

The Nephites were taught to defend themselves against enemies, even to the point of bloodshed if necessary. But they were also taught never to be the aggressors—never to raise a sword except against an enemy, and only to save their own lives.