To be fair:

Wisconsin, according to https://en.wikipedia.org/wiki/Wisconsin , has a population of nearly 5.8 million people.

Which, according to https://en.wikipedia.org/wiki/List_of_European_countries_by_population , means that Wisconsin has a larger population than Denmark, Finland, Norway, and Ireland.

If you're from Pennsylvania, with a population of 12.8 million, you're from a state with a larger population than Belgium, Greece, Portugal, and Sweden.

And if you're from California, with its population of 39.2 million, well, then you're from a state with a larger population than Canada (at 35.1 million). Italy's population (at 60 million) is only 50% greater than your home state, and the U.K. (at 65 million) and France (at 67 million) are't that much further ahead.

On some level, the ridiculous thing is NOT that someone would say, to people, in an international context, that they were from Wisconsin and expect people to know where that is. The ridiculous thing is that someone would say, in an international context, they're from Sweden or Ireland and we're all expected to know where that is.

At least by population, being from Wisconsin, USA is pretty analogous to being from Ireland, EU.