tended as a restraint on State interference with
federal instrumentalities. Conversely, the Court's recent return to
Marshall's conception of the powers of Congress has coincided with a
retreat from the more extreme positions taken in reliance upon McCulloch
_v._ Maryland. Today the application of the supremacy clause is
becoming, to an ever increasing degree, a matter of statutory
interpretation--a determination of whether State regulations can be
reconciled with the language and policy of federal enactments. In the
field of taxation, the Court has all but wiped out the private
immunities previously implied from the Constitution without explicit
legislative command. Broadly speaking, the immunity which remains is
limited to activities of the Government itself, and to that which is
explicitly created by statute, e.g., that granted to federal securities
and to fiscal institutions chartered by Congress. But the term,
activities, will be broadly construed.

Clause 3. The Senators and Representatives before mentioned, and the
Members of the several State Legislatures, and all executive and
judicial Officers, both of the United States and of the several States,
shall be bound by Oath or Affirmation, to support this Constitution; but
no religious Test shall ever be required as a Qualification to any
Office or public Trust under the United States.

Oath of Office

POWER OF CONGRESS IN RESPECT TO OATHS

Congress may require no other oath of fidelity to the Constitution, but
it may superadd to this oath such other oath of office as its wisdom may
require.[106] It may not, however, prescribe a test oath as a
qualification for holding office, such an act being in effect an _ex
post facto_ law;[107] and the same rule holds in the case of the
States.[108]

NATIONAL DUTIES OF STATE OFFICERS

Commenting in The Federalist No. 27 on the requirement that State
officers, as well as members of the State legislatures, shall be bound
by oath or affirmation to support this Constitution, Hamilton wrote:
"Thus the legislatures, courts, and magistrates, of the respective
members, will be incorporated into the operations of the national
government _as far as its just and constitutional authority extends_;
and it will be rendered auxiliary to the enforcement of its laws." The
younger Pinckney had expressed the same idea on the floor of the
Philadelphia Convention: "They [the States] are the instruments upon
which the Union must fre