This is offensive as this "pirate" stereotype attempts to put a label and thus attempts to conceal an unfortunate situation thrust upon an entire nation of people who are forced to accept the nuclear waste and robbery of their waters' fish by so-called "developed nations". The "ninja" stereotype makes light of a cultural and religious expression and the history behind it. Considering how little those in the West care to examine the truths behind such stereotypes, these are sensitive topics that need honest and truthful dialogue rather than to be used to ridicule marginalized peoples, nations, cultures, and religions. Respect is thus appropriate when handling these topics or else don't use them at all.
Dude, no one cares. It's supposed to be a joke picture. The artist is Scandanavian, and therefore has a different type of humor than other people. She's not trying to offend anyone, she's just showing humor through events that have occurred. Denmark is an idiot type of character in this comic series, and does indeed revert to stereotypes, but other people don't, so get over it.
That angers me D:<
نينجا XD