Why is Sam Hazzard a valuable resource?

Sam was a valuable resource because of his enormous background of military and political knowlege.

But Sam Hazzard's principal hobby was listening to shortwave radio. He was not a ham operator. He had no transmitter. He listened. He did not chatter. He monitored the military frequencies and the foreign broadcasts and, with his enormous background of military and political knowledge, he kept pace with the world outside Fort Repose. Sometimes, perhaps, he was a bit ahead of everyone.