Iran since the Islamic revolution has employed the tactic of arresting Westerners in a bid to extract concessions from its foes, in a strategy of "hostage diplomacy" that has long presented Europe and the United States with a dilemma, observers say. Iranian authorities this week released two French nationals, Cecile Kohler and Jacques Paris, from jail in Tehran after more than three years. They had been convicted on charges of espionage but their families said they were innocent tourists unwittingly caught up in a wider game being played out between Tehran and the West. For in-depth analysis and a deeper perspective, François Picard welcomes Tara Kangarlou, Author, Award-Winning Global Affairs Journalist and Adjunct Professor in the Bachelor of Science in Foreign Service (BSFS) at Georgetown University.