For the younger folks: Kerry got some seriously badass medals for his military service in Vietnam. People who had been on the same boat as he did, but at a different time, worked with the Republican party to claim that he hadn’t really done what he did. The press ate this up, and distributed it widely, costing him public support and likely the election.
Crayons is a brotherly insult. Marines own it and make jokes with it because they know their sibling services use it the same way their brother would, with a smile and expecting the same back at them.
Corporal Camera would work though.