Should public school officials have the right to prevent students from wearing pro-American garb on Cinco de Mayo? This question has been at the heart of a California court battle between the Morgan Hill Unified School District and students who were told by a principal and assistant principal that they could not wear American flag t-shirts on the Mexican holiday back in 2010. Following the incident, a lawsuit against the district was launched by the students and their families. This week, the case came to a close, with a federal judge ruling against the students — a blow that is...