In reply to Scott Bradford.

I believe iThemes security does not like the wget user agent. A way to get around this is to add --user-agent="Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/34.0.1847.116 Safari/537.36" (or some other user-agent) to the end of the command.