Public Policy degree?

Hi! I have always been more inclined towards the humanities field. I attend the University of Michigan and wanted to apply to the Gerald Ford school of Public Policy. Ideally, Id want to work in foreign affairs and get involved in diplomacy. However, I have been hearing degrees which are in the social sciences aren’t marketable in the job market right now. My parents are hesitant as well because they want me to do a STEM degree. I was just wondering if my job aspirations are too naive/unattainable?