al States, are
citizens of the United States; or,

_Fourth._ That it is left to each State to determine what free
persons, born within its limits, shall be citizens of such State, and
_thereby_ be citizens of the United States.

If there be such a thing as citizenship of the United States acquired
by birth within the States, which the Constitution expressly
recognises, and no one denies, then these four alternatives embrace
the entire subject, and it only remains to select that one which is
true.

That the Constitution itself has defined citizenship of the United
States by declaring what persons, born within the several States,
shall or shall not be citizens of the United States, will not be
pretended. It contains no such declaration. We may dismiss the first
alternative, as without doubt unfounded.

Has it empowered Congress to enact what free persons, born within the
several States, shall or shall not be citizens of the United States?

Before examining the various provisions of the Constitution which may
relate to this question, it is important to consider for a moment the
substantial nature of this inquiry. It is, in effect, whether the
Constitution has empowered Congress to create privileged classes
within the States, who alone can be entitled to the franchises and
powers of citizenship of the United States. If it be admitted that the
Constitution has enabled Congress to declare what free persons, born
within the several States, shall be citizens of the United States, it
must at the same time be admitted that it is an unlimited power. If
this subject is within the control of Congress, it must depend wholly
on its discretion. For, certainly, no limits of that discretion can be
found in the Constitution, which is wholly silent concerning it; and
the necessary consequence is, that the Federal Government may select
classes of persons within the several States who alone can be entitled
to the political privileges of citizenship of the United States. If
this power exists, what persons born within the States may be
President or Vice President of the United States, or members of
either House of Congress, or hold any office or enjoy any privilege
whereof citizenship of the United States is a necessary qualification,
must depend solely on the will of Congress. By virtue of it, though
Congress can grant no title of nobility, they may create an oligarchy,
in whose hands would be concentrated the entire power of the Federa