Dora Bas Rivka Silver O'H
Nahum says woe to Nineveh, which he calls here the "city of blood," a term later used by Ezekiel to describe Jerusalem. (See Ezekiel chapter 22. The Book of Ezekiel appears earlier in the Bible, but Ezekiel lived about 200 years after Nahum.) Here come invading horses, chariots and armed soldiers! There will be no end to the casualties in Nineveh. Nineveh was very smooth - they could sweet talk other nations into a false sense of security before conquering them. G-d will expose them to the other nations. (The prophet compares Nineveh to a seductress and her punishment as one given a harlot.) G-d will make them disgusting, like dung. Anyone who sees Nineveh in this degraded state will comment how far they have fallen, but nobody will feel bad for them because they oppressed everyone else..
Nineveh is no better than Alexandria (here called No-Amon); they were a great and mighty city, but they were also conquered by Nebuchadnezzar. What happened to Alexandria will happen to Nineveh; Nineveh will disappear as if they never existed. The fortresses of Nineveh will be easy to conquer, like shaking a fig tree and having the ripest figs just fall off, into Babylonia's mouth.
The army of Nineveh will be as easily overcome as the women of the city. The enemy will take the land and set fire to it. The people will stockpile water for the duration of the siege, they'll try to fortify their strongholds, but it will do no good. The fire and the sword will overpower them like locusts tear through a field of crops. (Nahum then expounds upon the locust metaphor for a few verses.)
The leaders and warriors of Assyria are fast asleep - that is, powerless in the face of the Babylonian onslaught. The people are disorganized with no one to rally them. No one mourns for Assyria - they didn't exactly make friends. They oppressed everyone else, so the other nations are glad to see them gone.