The President never "demanded" anything from Zelensky, nor did he demand that the Bidens be investigated. He specifically asked if, as a favor, they would look into the firing of Viktor Shokin.
#8. Re a request for a foreign govt to investigate a US citizen - what makes US citizens exempt from criminal and subversive investigations any place in the world. Phillip Agee and his American cohort, Yahoo/Newsweek writer Mark Hosenball, were investigated and thrown out of England for subversion.
We had hardcore pro-communist journalists in Nam who were kept under some watch and a few were expelled for various reasons including Mr. Hanoi “Don Luce”.
You can be damned sure that the French Surete’ kept John Kerry under surveillance during his trips to the No. Vietnamese/VC embassies/legations in Paris and possibly Versailles.
The same for American SDS leaders who went to Europe to forment student riots there (France, Germany, possibly England). Americans were involved in the KGB “Campaign for Nuclear Disarmament” in England and CND representatives came to the US to agitate here (I knew about them through communist sympathizer contacts).
Interpole watches American criminals/suspects in foreign countries, at out request, all the time. No big deal.