The book of Micah describes God's coming judgment on Israel because of its rebellion. But God will show mercy and will one day gather and restore his people and all nations to the land. God will rebuild Jerusalem, defeat evil forever, and set a messianic King to rule over the people and bless all the nations.
Before that can happen, though, God must confront and judge evil from among his people. Then he can show mercy and fulfill his covenant promise to Abraham and bless all the nations through Israel. His ultimate purpose is not to destroy Israel but to redeem and save the world.