Conversion and Support of Israel

I’m incensed over the Rotem bill currently on the floor of the Knesset. I fully endorse the statement of the United Jewish Federations that this bill, which would give full control over conversions in Israel to the rabbinate, could drive a deep wedge between Israel and Diaspora Jews. What right do the Orthodox rabbis have to control such a global and sensitive issue in a country that belongs to all streams of Judaism?