No, there isn't a "right" of return. It's true that hundreds of thousands of Palestinian Arabs left to neighboring Arab nations during the 1948 war - but at the same time, hundreds of thousands of Jews left those Arab nations and migrated into Israel. Israel took them in with arms wide open, of course, and they successfully rebuilt their lives in Israel. The Arabs who fled to Jordan, Syria, and Lebanon did not have a similar fate - those Arab countries put them into crowded camps and denied them basic human rights (did you know a Palestinian citizen's vote in Jordan is worth half the vote of Jordanian citizen?). The Arab world has been using the refugees as political cards against Israel for decades now.