Yep. Good one. Remnants of good, funny photo / poster / cartoon humour in WW2 are hard to find. Re: non funny newspaper cartoons - for history buffs There is a decent collection here: World War II Through Cartoons | McCord Museum and from the other side's perspective, Lustige Blätter here: WWII Nazi Cartoons
From Wikipedia: A common stylisation of Erin Go Bragh, in a pseudo-Gaelic font. Erin Go Bragh (sometimes Erin Go Braugh) is the Anglicisation of a Gaelic phrase used to express allegiance to Ireland. It is most often translated as "Ireland Forever"[1] and pronounced /ˌɛrɪn ɡə ˈbrɔː/.