Yes, there are jokes that get missed. But so many are understood that it was still funny.
America had its own influential comic book industry since the early twentieth century, so it never got into importing them. For most of Europe (and beyond) the comics made in France and Belgium and translated in the vernacular were the absolute cornerstone of comics for most of the previous century.
A lot of European kids who grew up in the twentieth century know about the American Old West through reading a cowboy comic (Lucky Luke) made by a Belgian, and first heard of Julius Caesar and the Roman Empire through Asterix.