The majority of commentators take this verse as continuing to describe the attackers, though Good News Translation seems to treat it as referring to the defenders by linking it with the first part of verse 5. The majority view seems more probable. Since the assault on the city walls is not mentioned until verse 5, the streets and squares here must refer to areas in the suburbs of Nineveh that were outside the main fortifications. The squares were more open areas where the chariots would have more room to turn (compare New American Bible “wheel in the squares”).
The terms used for the movements of the chariots are very vivid. (See comments on verse 3 for other ways to translate chariots.) For rage Good News Translation uses the expression “dash wildly.” The actual type of movement involved is not so important as the picture the words create of a situation which is frantic and disorderly. Translators should try to create a similar impression by the terms they choose; for example, “run in a confused way,” “race madly,” or “run in an uncontrolled way.”
They gleam like torches, they dart like lightning: these words probably refer again to the way the sun was reflected from the polished metal of the chariots. A torch was a long pole with rags that were soaked in olive oil and then attached to one end of the pole. When the rags were set on fire, the torch gave out light. The comparison with torches stresses brightness, and the comparison with lightning stresses both brightness and speed. These two sentences can be rendered “They gleam like the light from flaming torches, and dart about like flashes of lightning.” The word dart refers to very fast movement, first in one direction and then in another. In languages which do not have a single term for the idea of dart, translators may have to use a phrase; for example, “they rush in one direction and then in another.”
Quoted with permission from Clark, David J. & Hatton, Howard A . A Handbook on the Book of Nahum. (UBS Helps for Translators). New York: UBS, 1989. For this and other handbooks for translators see here .