Unclean Exile

My source today is Jacob Neusner's Judaism: The Evidence of the Mishnah. I'm not in the mood to look for the date.

Here are a few sentences that intrigued me:

"Uncleanness, which above all endangers the cult and must be kept away from the Temple, is what characterizes all lands but the holy Land...The lands of the Gentiles are unclean with corpse uncleanness. So death lies outside the holy Land, with consequent uncleanness" (225).

I remember reading something similar in Fishbane's Biblical Interpretation in Ancient Israel, but I forget where exactly.

So do Jews believe they are unclean in exile? This is an important question, since they've been in exile for a long time. For years, numerous Jews have managed to make their home outside of the holy land--in biblical, Hellenistic, rabbinic, medieval, and modern periods. What's their religious status, according to Judaism? I'm not sure if the Mishnah offers answers, for it related to the land of Palestine. The Talmud may. I don't know.