"We must remember that even with the destruction of the First Temple, and certainly with that of the Second, there was not a massive exile of our people from the land.
However, if in a practical way the situation of the nation changed little with the Destruction, as long as the Temple stood, Jews outside of the land were only a “Diaspora”, a “scattering” of people who happened to live in another country.
The loss of national independence made little change in the situation, as our people had complete national independence in its own land for a relatively short period anyway.
But upon the destruction of the Temple there came that feeling of orphancy which is implied in the concept of exile.
The far-flung communities of Israel, which had possessed a center toward which all life was directed, were suddenly no longer in a state of mere temporary absence (which would eventually be terminated), but, in a deeper sense, in exile, under the yoke of “foreign slavery” in every land, including the land of Israel.
Therefore, the sufferings of Israel are unlike those recorded in the history of any other nation.
The destruction of the Temple was the “expulsion of the Divine Presence” from Israel, and all the subsequent sufferings of Israel are understood as merely a repetition of that same event, a loss continually felt by a people lacking the center of its being."
From “Tisha B'Av: Destruction and Redemption” by Rabbi Adin Steinsaltz
