Recently an American Jew asked me the following question, in view of the news concerning recognition of conversions into Judaism carried out in the Israeli army (IDF):
Hey, let me ask you something. My wife told me that Israel is in the middle of redefining who is a Jew, and that Reform/secular/assimilated people like me wouldn’t be considered Jews any more. Is that going to affect the Law of Return?
My reply to him was:
The law of return won’t be affected, but ability to marry in Israel will be affected, because the Chief Rabbinate has legal monopoly over marriages of Jews (corresponding bodies have monopolies over Christians, Moslems and Druze) and the scandal over recognition of conversions into Judaism (the actual subject worrying your wife) is relevant to getting recognized as Jews by the Chief Rabbinate.
People, who cannot marry in Israel, usually fly to Cyprus to get married there, and then their marriage is recognized in Israel. I have a cousin, who married in Cyprus, just because she was disgusted by the Chief Rabbinate.
The Law of Return explicitly covers non-Jews - if they have Jewish relatives (one Jewish grandparent or a Jewish spouse is enough).
As things look like, few years from now, civil marriages will be possible in Israel, because the group of people, covered by the Law of Return yet cannot marry in Israel, is growing each year (most of them are immigrants from the former Soviet Union and their descendants).