In an odd inversion, the grand project of the world's Jews, the State of Israel considers all Jews, wherever they are, to be part of its, Israeli diaspora.
It all started with Zionist ideology. Zionist logic follows these steps:
1) The State of Israel is the rightful heir of the ancient Israelite kingdom of two millenia ago.
2) All Jews today are descendants of the ancient Israelites and have therefore maintained their forbears' rights to the Land of Israel.
3) Israeli Jews exercise these ancient rights to the Land on behalf of all Jews.
4) Therefore, all Jews who choose to remain outside the Land, are living in exile or "the Diaspora".
The appearance of the word "diaspora" in the English language coincided with the birth of political Zionism in the late 19th century. The Greek word was used to describe the Babylonian exile of the Bible and was used specifically in relation to the Jews.
The State of Israel's first leader, David Ben-Gurion, claimed the word "Israel" for the new state. In correspondence with the Chicago Jewish thinker Simon Rawidowicz, he declared that, with the formation of the Jewish state, Jews around the world could no longer call themselves "Israel." That word was now the sole property of the Jewish state; "Israel" means "the State of Israel." Ben Gurion was successful; this is the popular meaning of the word "Israel" today.
Ben Gurion wasn't so successful with pinning the word "diaspora" on the rest of us. The only ones who use that word are Israelis, and mostly Israeli officialdom at that.
The State of Israel takes its responsibilities for its fellow Jews seriously. It even has half a cabinet posted allocated for staying in touch. But wouldn't it be nice if they could spell the word correctly (top left corner).
Greek is hard enough as it is.