Translation analysis: The Book of Mormon adds a phrase to this verse:
Isa. 2:14 And upon all the high mountains, and upon all the hills that are lifted up.
The addition is that it becomes the people and nations that are lifted up. Once again, this fits roughly into the context of the Isaiah’s discourse, but not precisely into the meaning. Isaiah does cite the people, but does so just as the cedars of Lebanon and the high places are symbolic (the high towers and fenced walls representing the cities, and therefore the people in them). The specific bringing low of the people occurs in verse 15 in Isaiah, thus becoming a repetition in the Book of Mormon where it is a continuing symbolic set in Isaiah.
Scriptural analysis: Verse 14 is more specific where verses 13 more symbolic. Nevertheless, while the Book of Mormon is being more specific about the Lord conquering all people who might be lifted up, we should not miss Isaiah’s reference to the gods of those peoples represented by the phrase “upon all the high mountains, and upon all the hills.” In Biblical terms, the references to “high places,” specifically trees or gardens in the high places or the hills is a reference to Near Eastern worship that had representations of their gods in groves in the hills and mountains. These phrases in particular should be seen as being correlated with the more specific verses speaking of the destruction of the idols.