Overall Research Project Description Why some Arab states signed normalization agreements with Israel while other Arab states did not? What explains variation in the behavior of Arab states toward Israel? The American role in altering the calculus of MENA regimes toward Israel is well observed and assumed, but rarely measured. In this research, I propose costly signal argument linking US high-level leader visits and in-person diplomacy to the behavior of MENA regimes toward Israel. I argue that more exchanged visits between US and MENA leaders are associated with more moderate behavior of MENA regimes toward Israel. My approach yields a cross-sectional time-series dataset using data on US diplomatic visits and measures of UNGA voting affinity, latent interstate hostility, and bilateral trade across 22 MENA countries from 1950 to 2020. I find considerable empirical support to the theoretical prediction: diplomatic visits correspond to decreasing distance between the UNGA ideal points of MENA states and Israel and increasing volumes of bilateral trade with Israel. I also find no evidence that these associations are conditional on the amount of received aid from the US as a compensatory material benefit. These findings advance new empirical knowledge about the scope and magnitude of American diplomacy in shaping the politics of the MENA region.