What is the meaning of "v'Hayu Amim Misrefos Sid"?
Radak: The nations in Machaneh Ashur will be rocks burned for plaster [or thorns that people burn].
Radak (24): Some explain this entire Parashah to discuss the days of Mashi'ach 1 .
Malbim: Plaster keeps its heat for many days, but it does not flare up quickly. Dry thorns burn quickly, but they do not keep their heat. The nations will resemble plaster, which keeps its heat, and also cut thorns. I.e. Hashem's fire will burn them easily, and Chatas of a Nasi in them many days.
Radak (24): What I explained (it refers to striking Machaneh Ashur) is correct.
What are "Kesuchim"?
Rashi: They are cut. The Targum of "Lo Sizmor" (Vayikra 25:4) is Sichsach. Radak - when thorns are not cut, rather, they are attached [to the ground], they are connected to water, and do not burn quickly. When they are cut and dry, they burn quickly. So the plague [in Machaneh Ashur] will be sudden.
