Why did he say "Mah he'Arim ha'Eleh"?
Malbim: They will not be able to produce their quota (refer to 9:11:2:1).
What is "Eretz Kavul"?
Rashi: It is like shackles. It is a muddy land in which the foot sinks and is shackled in it.
Radak: It is closed. People did not pass through, because it was inferior.
Radak citing Shabbos 54a: It does not bear fruit. Rav Nachman bar Yitzchak said, it was a Chutmun (sandy) land. One who walks in it sinks in it, and it is like shackles. Therefore it does not bear fruit.
In Divrei ha'Yamim II, 8:2 it says that Chiram gave to Shlomo 20 cities is his land for Yisraelim to settle in!
Radak: Each gave to the other, in order to strengthen the Bris between them. Here it mentions what Shlomo gave to Cherem, and there it mentions what Chiram gave to Shlomo.
Malbim: Chiram was not pleased with them, so he returned them to Shlomo. Shlomo settled Yisraelim in them to work the land, and they gave their quota to Chiram, to continue the connection between [Shlomo and Chiram].
