The USCCB has authority only from the bishops who give it their own.
Wrong. Canon law provides certain authorities to national conferences of bishops.
CIC,
vatican.va/archive/ENG1104/__P1L.HTM
Can. 455 §1. A conference of bishops can only issue general decrees in cases where universal law has prescribed it or a special mandate of the Apostolic See has established it either motu proprio or at the request of the conference itself.
§2. The decrees mentioned in §1, in order to be enacted validly in a plenary meeting, must be passed by at least a two thirds vote of the prelates who belong to the conference and possess a deliberative vote. They do not obtain binding force unless they have been legitimately promulgated after having been reviewed by the Apostolic See.
§3. The conference of bishops itself determines the manner of promulgation and the time when the decrees take effect.
§4. In cases in which neither universal law nor a special mandate of the Apostolic See has granted the power mentioned in §1 to a conference of bishops, the competence of each diocesan bishop remains intact, nor is a conference or its president able to act in the name of all the bishops unless each and every bishop has given consent.
The USCCB does not have authority to override liturgical rubrics.
Depends upon the specific conference. The USCCB DOES have the ability to legitimately override certain norms, as granted by the Holy See in various places. Specifically, postural issues for particular national conferences are a standard authority, granted by the Roman GIRM, and thus the reason that national versions of the GIRM do in fact differ from each other, once passed by 2/3 vote of that National Conference’s membership in plenary coucil.
That is reserved to the Holy See.
It is reserved to the Holy See to approve local overrides to the universal rubrics. Rome has done so for several conferences in specific cases, for example, the authorization for the Far-east conferences to permit the bright red cassocks to clerics in those nations, as that color is in fact the local traditional color for clerics of several faiths.
The USCCB, the AusCCB and the CCCB have all been granted permission to make standing reception the norm; in fact, that is a universal permission to the conferences to make that decision, NOT the local bishop. Some conferences never adopted it; others made it the norm; it is relatively recently that Rome altered the authority such that kneeling reception may not be prohibited. (But standing reception may be declared either normative or prohibited, while kneeling may be declared mandatory, or non-normative, but may not be prohibited.)
Lots of elements of liturgy are under the discretion of the national conferences; they are not delineated clearly in canon law, but the means by which that authority is granted are.
The USCCB can’t override the CDWS without Papal approval; it is within the competence to enact such legislation, and that legislation is subject to veto by the pope. They have not enacted such legislation, and should they ever do so, it will require papal approval before they may publish the legislation and/or act upon it.
