McGrath,
Without that precipitating factor there is no reason to believe it would have happened.

An alternative view.
"It is the custom to say that Zionism was responsible for this (expulsion) development. However, the region's anti-Semitism would have developed even without the rise of the state of Israel because of Arab-Islamic nationalism, which resulted in xenophobia. The fact that these events have been obscured has served in the campaign to delegitimize Israel, and therefore to a large extent, the same population that suffered this oppression. The fate of Palestinian refugees, their proclaimed innocence, and the injustice they endured form the main thrust of this delegitimization. The Jewish refugees have suffered more than the Palestinian refugees and undergone greater spoliations. However, they became citizens of the countries of refuge, especially Israel and France, while Palestinians were ostracized from the Arab nations. -
http://jcpa.org/article/the-expulsion-of-the-jews-from-muslim-countries-1920-1970-a-history-of-ongoing-cruelty-and-discriminatio