“During Nazi occupation, the Dutch wore secret safety pins to symbolize unity”
I’m Dutch and my grandparents lived through the war and I have never heard of this. Your only source of information is a Canadian book referencing an American propaganda film, released in 1942, which tells a fictional story about the French and Dutch resistance movement. I can’t find anything to corroborate your story in Dutch sources on this time period and subject. So… lovely story, but it’s based on pure fantasy and shouldn’t be presented as fact.