On creation of the state of Israel, there were over 500.000 Jewish refugees from various Arab countries that were expelled.
That 500,000 number comes from counting Jewish immigrants from Arab lands who arrived in Israel between 1948 and 1972. The only reason for making the timeframe so long is so that French Jews who quietly and voluntarily emigrated to Israel when Algeria became independent can be included. It's not an accounting of people who were forced out at gunpoint and ethnically cleansed from their 1,000+ years old communities, although there were a lot of them.
Anyway, you can't use what happened to people in Algeria in 1968 to justify what happened to people in Palestine in 1947. You can't even use what happened to people in Germany in 1944 to justify it, although those events makes it at least understandable.