Those are overall visitations. There's no indication that they're vacationing or tourists. Does Chicago have more global business interests than Rome?
My Mother went to Chicago every year for Emergency Room training. Was she a tourist? Or was she there because Chicago, for all it's problems, has one of the most competent and practiced set of ER doctors in the entire country?
If you were to take exports as a good proxy for “global business interests”, then the USTR would show you that Chicago exports 57.9B in goods, making Chicago’s exports almost 1/3 of Rome’s entire GDP.
Does it really matter? Both tourism and business fall under the same ESTA Visa Waiver programme. In both cases you have people visiting without any visa but just an online application at cpb. I dont even think they stamp passports anymore during entry in the US. It's all digital now.
My Mother went to Chicago every year for Emergency Room training. Was she a tourist? Or was she there because Chicago, for all it's problems, has one of the most competent and practiced set of ER doctors in the entire country?