Of course, by “born on U.S. soil,” you mean also, “of citizen parents.” Otherwise, “natural born citizen” means “Anchor Baby.” And then you immediately have to deal with the question: Is an Anchor Baby more of a “natural born citizen” than a child of a citizen parents or parent born just across the border in Canada???
Yeah you do. There’s the separate but related issue of whether the 14th Amendment covers children born of aliens, it if were resolved in the negative would render moot the question of whether they are natural born citizens.