InList Operator in Where Clause ---Is it "And" or "Either of"...?

I have a table like this.

If I run the variable like this

=Count([Country]) Where (City InList("New York";"London"))

The answer is 1, right?

It will be US 2, who has both of 2 items in the list.

Or it will be 3?

Because UK, US, US2 all have either one of the items in the list.

InList means..."either one of" the items in the list?

I would be extremely grateful if somebody could clarify on this point...

I am getting confused here...