In section 45 of the Doctrine and Covenants we have some eschatological verses in which the Lord compares his second coming to the things that happened in Jerusalem after his death in the meridian of time and at the time of the American Civil War. The thing is, it is kind of hard to tell what verses refer to the events in Jerusalem, or the Civil War, and which refer to the last days. I decided it might be helpful to do a breakdown.
Jesus introduces the comparison in vs 16, "And I will show it plainly as I showed it unto my disciples as I stood before them in the flesh, and spake unto them saying..." In other words our minds should be transported back to when Jesus was with his disciples who had asked him about his return. The footnote there takes us to Matthew 24: 3-26. We are watching him prophecy to those disciples about the destruction of Jerusalem. "And now ye behold this temple which is in Jerusalem, which ye call the house of God, and your enemies say that this house shall never fall. But, verily I say unto you, that a desolation shall come upon this generation as a thief in the night, and this people shall be destroyed and scattered among all nations." (v 18-19) Then he goes on to prophecy of the destruction of the temple, and the scattering of the Jews. (v 20) Finally he sums up the flashback by saying "And it shall come to pass, that this generation of Jews shall not pass away until every desolation which I have told you concerning them shall come to pass." (21).
We know from history that this prophecy came true. A false Messiah rose up and stirred the Jews up into revolt against Rome. In retaliation the Romans desolated Jerusalem, tore down the temple, and scattered the Jews in 70 AD.
In the verses that follow Jesus compares the destruction of Jerusalem in 70 AD to the time the Saints are currently in. He talks about the "times of the Gentiles" (v. 25) which will be characterized by "wars and rumors of wars, and the whole earth will be in commotion." (v 26) But during these perilous times, "And when the times of the Gentiles is come in, a light shall break forth among them that sit in darkness, and it shall be the fulness of the Gospel."(28). So what time period are we in now? The time of the restoration of the gospel.
He starts then to prophecy of about the generation existing in 1830. "In that generation shall the times of the Gentiles be fulfilled. and there shall be men standing in that generation, that shall not pass until they shall see an overflowing scourge, for a desolating sickness shall cover the land." There were actually several epidemics that occurred during the 1830-1850s in the United States. There were Yellow Fever epidemics in 1833 and 1851 and Scarlet Fever in 1847 and 1885. For most of these, the Latter Day Saints were spared because they had already left the main body of the United States and were isolated in the West. "But my disciples shall stand in holy places, and shall not be moved." (v 32.)
He also prophecies of war, "...yet men will harden their hearts against me, and they will take up the sword, one against another, and they will kill one another." (v. 33) It is easy to see this as a prophecy of the Civil War, especially because it says they will take up the sword "one against another," rather than against an invading army or an enemy.
So far we have seen prophecies of the destruction of Jerusalem, and prophecies of the 19th century. After these prophecies, God finally refers to the last days. These prophecies are much more vague. "...he that feareth me shall be looking forth for the great day of the Lord to come, even for the signs of the coming of the Son of Man. And they shall see signs and wonders...And they shall see blood, and fire, and vapors of smoke." (v. 39-40.)
"And before the day of the Lord shall come, the sun shall be darkened and the moon be turned to blood, and the stars fall from heaven." (v. 42) These descriptions sound a lot like the Book of Revelation symbolic prophecies, rather than the specific prophecies about the fall of Jerusalem and the Civil War. From here on out he describes Jesus' appearance in a cloud, (v 44) the rapture (v. 45) and the resurrection (v. 45). He also describes the judgement on the wicked. Those who willfully rebelled shall be "hewn down and cast into a fire." (v.50) The Jews will recognize their fallen Lord, (v. 51-52) and heathen nations, who had no chance to learn of Christ shall be redeemed (v.54) Finally, he hints that he is merely recounting what has already been revealed in the New Testament (presumably the Book of Revelation) when he says, "And now, I say unto you, it shall not be given unto you to know further concerning this chapter, until the New Testament be translated, and in it all these things shall be made known." (v. 60).
In summary, not all the dire prophecies in D&C 45 are prophecies of the last days. Some are about the destruction of the Jews in 70 AD, and some are about the coming Civil War in (1860). The ones that are about the second coming and beginning of the Millennium echo the symbolic prophecies we already have in the Book of Revelations. That are meant to assure us that even though Satan fights against the Saints, the Lord and his disciples will ultimately triumph.