Where is the line drawn between 'Thriller' and 'Espionage'?

[Tony]

Are they the same genre? Is The Hunt for Red October a novel of espionage or a thriller? Are Olen Steinhauer's novels prior to the Milo Weaver books thrillers?

[Alan]

Hi Tony. The line between Thriller and Espionage is very complex. I can't tell whether my books are thrillers or espionage, or counter terrorism espionage thrillers. I don't exactly know which genre I fall into and its driving me crazy! Alan Kiernan