In this week's Monday Briefing, MEI experts Gonul Tol, Gerald Feierstein, Alex Vatanka, and Marvin G. Weinbaum provide analysis on recent and upcoming events including the victory of Turkish President Erdogan's "Yes" constitutional referendum campaign to increase his powers, Secretary of Defense Mattis' trip to the Middle East, the entry of 1,600 candidates for the upcoming Iranian presidential elections, and the alarming violence in Pakistan against accused "blasphemers".