Ten Reasons the Merchant Marine is Failing

Port State Control is done by the Port State, not the Flag State, thus any PSC on an American flag vessel is done by a foreign entity in a foreign port:

When USCG inspect a US flag vessel in a US port or anywhere, it is as the Flag State Authority.
Here is the definition of Flag State Control as issued by MPA Singapore:

And the difference of the two in terms of ILO’s MLC’06 , which USA is not a signatory to, but have to comply with when US ships visit foreign port:

Here is a list of the Classification Societies that is approved by USCG to perform inspections on their behalf and which inspections they are approved for:

ABS already issues the load line, new construction plans in conjunction with the USCG Marine Safety Center NAVARCHS, and cert the hull, machinery and issue the majority of statutory certs on behalf of the CG and approve repairs on behalf of and in addition to the CG for compliance with the Machinery and Hull certs soI do not understand the proposal? Second the SIP worked sometimes and almost exclusively for OSVs and other limited tonnage vessels. ACP-MSP though desireable on one hand for industry is also a major reason for skillset erosion among coastie inspectors which makes them less competent and those two programs have been under scrutiny and criticism…SIP would not and should not be instituted for unlimited tonnage, fox in the henhouse scenario.

I think you are referring to larger vessels but this is LITERALLY what Subchapter M is - Subchapter M just kicked into effect yesterday (7/20/2018) after about 10 years of planning . Obtaining a COI for Towing Vessels, of which there are 5,500 in the United States. You have the option of going USCG for your inspection or going to a private USCG approved TPO (Third Party Organization).