Found this online, online copy of "Uncomfortable Questions for Comfortable Jews" it basically explains what Kahane said in the lecture.
the difference is between a ger toshav (resident non-Jew in Israel) and ger tzedek (convert).
http://www.scribd.com/doc/2672202/Uncomfortable-Questions-for-Comfortable-Jews-by-Meir-Kahanepage 81
"But the Bible tells us to love the stranger. The Bible declares that there shall be one law for you and the stranger."Again, even if it were true that the Hebrew word in the Bible— ger — which is wrongly translated "stranger," meant the
non-Jewish foreigner, of course it would mean that one should not oppress or persecute that non-Jew who is allowed to live in Israel as a
ger-toshav, resident stranger. That one must help him and feed him and heal him and treat him with decency and mercy and respect. It does not mean that he must be given the right to be equal politically, a citizen, one who has a say in the character and running of the state.But more than that, the rabbis make it clear that the general use of the word ger in the Bible refers to what they term a
ger tzedek, a gentile who has converted and become a Jew. The warning is not to offend him or treat him in any way differently from the one who was born Jewish. And this is what is expressly stated in the Chinuch (Commandment 63):" 'And you shall not oppress or persecute a ger . . .' (Exodus 22). We are prevented from oppressing a ger even with words. And this is one of the seven nations who converted and entered our faith."And the rabbis (Torat Kohanim, Leviticus 19), on the verse, "And if a ger shall live in your land you shall not oppress him; as an ezrach (citizen) of you shall he be" (Ibid.). "'As an ezrach:' just as an 'ezrach' is one who accepted all of the Torah, so is a ger, one who accepted all the Torah. "And when the Bible uses the term ger in the context of the "stranger" and the Jews who were in Egypt, as in the verse, "And you shall love the ger for you were gerim in the land of Egypt" (Deuteronomy 10), the greatest of the Aramaic Biblical translators, Onkelos, who was himself a ger, a convert to Judaism, carefully and painstakingly uses two different words to translate ger and gerim, and thus to differentiate between the meaning of the two in the verse. Concerning, "And you shall love the ger," Onkelos says, "And you shall love the Giora (meaning convert to Judaism). But in translating "for you were gerim," he writes, "for you were dayarin [meaning "residents"] in the Land of Egypt." Of course the use of the word ger by the Torah refers to the stranger who converted to Judaism and who is now a full Jew. The Torah understood the danger of discrimination by "natural-born" Jews against the "new" Jew who, but yesterday, was a gentile. That is why the emphasis on the need to treat the ger — converted Jew —as yourself."