The territory occupied by the nation of Israel today is not the territory occupied by the Israel of the divided kingdom period. It is not the territory occupied by the nations of Israel and Judah when they were briefly united under the house of David. According to the prophets, it is also not the territory which will be occupied by the Israel of the future.
There is some land in common, of course. Territory has been gained (the Negev and the Gaza Strip, for example). But when Israel lost the Transjordan to Assyria, it never got it back. Moreover, few modern Israelis are descended from the people who occupied the northern kingdom when Amos prophesied against it.
We understand the prophets more accurately when we correctly identify their intended audience. Let me take a stab at that.