1)
Who will fear and be agitated?
1.
Radak: The nations. Malbim - they will fear to fight Yisrael, due to their great Shalom, and be agitated due to all the good [that Hashem does for Yisrael].
2)
For whom is all the good and Shalom?
1.
Radak: It is for Yerushalayim.
