Tuhia he tomokanga mō tēnei wāhanga - I te tīmatanga o te Pakanga Tuarua o te Ao i te Mahuru 1939, ka uru a Kopp ki te French Foreign Legion hei kaitiaki, ka whawhai ki te Pakanga o Parani i te marama o Mei-Hune 1940, i ora noa i te Blitzkrieg kaore i ora i te nuinga o ana hoa. I whara kino a Kopp, a, i mauheretia ia, engari i mawhiti i te hōhipera hōia, a, i taea e ia te hoki ki tana wae, inaianei he ope i hinga
, i waho noa atu o Marseilles i Akuhata. I te marama e whai ake nei, i tukuna a Kopp ki te tari matua o te Legion Foreign i Algeria, i reira i whakakorehia ai ia i te ope taua ka whakawhiwhia ki a ia he 80% reti.