2 Nephi 21

2 Nephi 21:6-8 The wolf also shall dwell with the lamb, and the leopard shall lie down with the kid, and the calf and the young lion and fatling together; and a little child shall lead them. And the cow and the bear shall feed; their young ones shall lie down together; and the lion shall eat straw like the ox. The sucking child shall play on the hole of the asp, and the weaned child shall put his hand on the cockatrice's den. They shall not hurt nor destroy in all my holy mountain for the earth shall be full of the knowledge of the Lord. Isaiah is using animals here as an allegory for people, indicated by the preceding verses about judging the poor and the meek. The animals represented are of two classes, the one, by nature, defenseless and the other, predatory and seemingly designed to prey on the first. The theme of judging righteously, in a way that does not inappropriately punish the poor is common throughout the Old Testament, indicating that it was as great a problem 3,000 years ago as it is today, where people who can afford to are not punished by the law to the same degree as those who can not afford to buy their way out.
Can we also understand from these verses that in the millennial day, these types of animals will also literally change their nature and cease to prey on one another? Sickness, death, corruption all entered the world by virtue of the fall, and the world started to bring forth thistles, thorns, briars and noxious weeds instead of fruits and flowers, but how much of that was already there, just not in the Garden of Eden? And if you take away a leopard's deadly grace, what is its purpose? If it doesn't need to run to eat, why would it do so? Would God make a creature so marvelously suited to pursuit and then change it in its paradisiacal state to be mild-mannered? Although, to that point, mankind seems uniquely adapted to violence and we are certainly hoping that will go away when Christ comes.

2 Nephi 20

2 Nephi 20:5-6 O Assyrian, the rod of mine anger...I will send him against a hypocritical nation.  We already know that the Lord has a history of using what might be considered wicked nations to punish what are supposed to be his righteous/covenant nations.  So which nations does he use today and does the United States qualify as one of his covenant nations?  This land is supposed to be choice above all other lands, free from kings, and a place of freedom as long as the inhabitants of the land worship Jesus Christ, but does that mean that we are also eligible for being scourged by wicked nations when we forget Christ?  And what is the danger inherent in winning against those wicked nations on our own terms and by our own might rather than looking to the Lord and repenting?  King Noah's people drove back the Lamanites and celebrated their own might only to be brought into bondage a couple of years later.

20:12 Wherefore it shall come to pass that when the Lord hat performed his whole work upon Mount Zion and upon Jerusalem (that is, after the Lord will have allowed Assyria to destroy Jerusalem), I will punish the fruit of the stout heart of the king of Assyria, and the glory of his high looks for he saith: By the strength of my hand and by my wisdom I have done these things. Wow.  poor guy.  He gets used and then punished for not recognizing that he is being used.  Still, he was a wicked fellow, but oddly, it's not saying that he will be punished for being wicked, but that he is being punished for thinking that by his own strength he had been able to overcome the Lord's covenant people.  But what non-believer anywhere would think, "A god I don't believe in is going to help me whup up on the people who do believe in him"? It seems like that may be a somewhat unreasonable expectation.

2 Nephi 19 (Isaiah 9)

2 Nephi 9:2,4 The people that walked in darkness have seen a great light;...For thou hast broken the yoke of his burden, and the staff of his shoulder, the rod of his oppressor. I often think that it's no wonder the Jews didn't accept Christ's assertion that this was him. He gave them the freedom that comes from knowing that earthly things pass away, rather than the freedom that comes from destroying their earthly oppressors, i.e. Rome.

9:11-12 Therefore the Lord shall...join his enemies together...and they shall devour israel with open mouth. For all this his anger is not turned away, but his hand is stretched out still. The imagery of the Lord, full of righteous anger, allowing the consequences of sin to punish his covenant people, but standing there, with his hand stretched out to rescue them if they will just reach out to him is rampant throughout the Old Testament and it is some of my favorite sources of understanding the nature of God. I think about my own self and my kids--when they are being bad and I'm punishing them, am I able to stand there with my hand out, ready for their sincere contrition? Through the rest of the chapter, this message is repeated several times, each time after he explains what they are doing wrong and what consequences of that they will be forced to endure, but he wants to make it clear that he is ready to forgive as soon as they are ready to repent.