Now, what does this mean? Is a visitor to the USA "subject to the jurisdiction" of the USA?
Can they be arrested and tried in our courts if they break our laws? Then they are subject to the jurisdiction of the United States.
Insomuch as if they are in the USA and break a US law, they are subject to the jurisdictional law where they break it, but they are not originally subject to our jurisdiction, they are subject to the jurisdiction of their home country where they are a citizen. You must read the sentence as a whole - it states and are, that is very important.
There is history and clarification on the 14th regarding the citizenship clause by the very person that submitted it, look upthread.
Is a visitor to the USA “subject to the jurisdiction” of the USA?