These dissenters tried to incite the Lamanites to war and failed; but another group of dissenters succeeded just two years later. How did Mormon (or his sources) know the reason for the first group’s failure? It is highly unlikely that anyone returned to report to Nephite headquarters that they had tried to incite warfare, but failed because the Lamanites were afraid. It is equally unlikely that whatever the Lamanites feared was dramatically altered in just two years. I read this passage as a touch of Nephite vanity that has entered history because we have records only from their viewpoint.
Chronology: The fifty-sixth year of the reign of the judges would be approximately 39 B.C.