The Congress shall have Power ... To provide for organizing, arming, and disciplining, the Militia, and for governing such Part of them as may be employed in the Service of the United States, reserving to the States respectively, the Appointment of the Officers, and the Authority of training the Militia according to the discipline prescribed by Congress;Make of that what you will.
Maybe just a matter of semantics, but it comes down the difference between “reserved” and “delegated”. “Reserved” means that the States retained this power for themselves, and exercise it on thier own behalf. “Delegated” means that the power rightly belongs to someone else, and the States are merely allowed to exercise it on someone else’s behalf.