The state of Israel is not the inheritance of promise. ALL the "lost" nations that came from the tribes are part of that promise.
As for the true identities of the nations today, the following is WAY oversimplified, but I'll sauce it.
A great deal of Scriptural study backs this up, and can be found here : cog49.com/ft.pdf
Deu. 32:8 - When the Most High divided to the nations … he set the bounds of the people according to the "number" of the children of Israel.
There are three generations of promise, and three generations of national inheritance.
The first was Jacob, whose national parallel was the promised land in the first day "age" (millennium).
The second generation is his 12 sons that became nations from 393BC and 1607 AD. They became Europe in this time, as appointed for the two thousand year (second) age, or "day."
The third generation was for Josephs two sons, which became the successive world powers, Great Britain and the US for most of the last four centuries.
The last inheritance was for Benjamin. Today, we call it Israel. But it is not. It is Benjamin.
And one of the most meaning stories about this is the inheritance of Benjamin is not part of the inheritance of Israel until (as portrayed in Scripture) David takes it.
The whole free world is STILL the other tribes, which only collectively make up "Israel."
The second advent is "salvation" coming as/with/in the son of man - which is after the "time of man (Adam)," - the six creation days - 6K years, from 4004BC to 1997AD.
After this "time of man" is the time of the son of man - recreated in us, collectively. This is what the "second coming" is all about - for us today, to learn. And this is what is happening all around us right here, right now.
Read about the history of three days, from pg 24 - 29 at the link; and the whole history of this deception in the US, in "Judah Defined" p58 to "Inheritance of Benjamin," p67.
You will also find the reasons for the deception, as they are cryptically told in the Bible.
But take your time and study it if you really want to understand this greatest deception never told.