Using a newly launched U.S. tourism commercial as a stimulus, this pre/post quasi-experimental study empirically tests the bleed-over effect of tourism advertising on public diplomacy measures. Metrics for both tourism and public diplomacy objectives were obtained after the commercial was viewed by a large, nationally representative sample of Australian adults. Confirmation of the bleed-over effect was found. Subgroup analysis further explains how the commercial affected various audience segments. Practical and theoretical implications for the use of tourism advertising as a tool for mediated public diplomacy are explored.