Portraits from Boston's 4th of July

On July 4th I went out to take some portraits of people coming to celebrate in Boston.  This was an emotionally charged public gathering with a heavy security presence after the Boston Marathon bombing.
When I set out to take pictures at an event it is hard to choose who to take a photo of when faced with a crowd of thousands.  I decided that I would ask everyone that was wearing an American flag if I could take their picture and allow them to present themselves as they wish.  Here are six images from that evening: