How do Mormon critics explain 2 Nephi 12:16? —Brian in Oregon

Many assert that Joseph Smith copied text right out of the King James Version of the Bible during those parts of the Book of Mormon in which Nephi quoted from the writings of Isaiah.

Although there are several subtle differences between the two, one notable difference between the Book of Mormon and the KJV Bible is found in 2 Nephi 12:16 (compare with Isaiah 2:16). For your convenience I have quoted both references below:

2 Nephi
"And upon all the ships of the sea, and upon all the ships of Tarshish, and upon all pleasant pictures."

Isaiah
"And upon all the ships of Tarshish, and upon all pleasant pictures."

Interestingly, the Septuagint (Greek) version of this same verse is translated as follows:
"And upon every ship of the sea, and upon every display of fine ships."

If not from the golden plates, where did Joseph Smith get the phrase, "And upon all the ships of the sea"? It is very improbable that a poor American farm boy would have had access to a Septuagint Bible in 1830.

I am a Mormon critic and I can't explain that. I also can't explain the NHM thing.