"The states were not “sovereigns” in the sense contended for by some. They did not possess the peculiar features of sovereignty,—they could not make war, nor peace, nor alliances, nor treaties. Considering them as political beings, they were dumb, for they could not speak to any foreign sovereign whatever. They were deaf, for they could not hear any propositions from such sovereign. They had not even the organs or faculties of defence or offence, for they could not of themselves raise troops, or equip vessels, for war.... If the states, therefore, retained some portion of their sovereignty [after declaring independence], they had certainly divested themselves of essential portions of it." - Rufus King, 1789
"The states were not “sovereigns” in the sense contended for by some. They did not possess the peculiar features of sovereignty,—they could not make war, nor peace, nor alliances, nor treaties. Considering them as political beings, they were dumb, for they could not speak to any foreign sovereign whatever. They were deaf, for they could not hear any propositions from such sovereign. They had not even the organs or faculties of defence or offence, for they could not of themselves raise troops, or equip vessels, for war.... If the states, therefore, retained some portion of their sovereignty [after declaring independence], they had certainly divested themselves of essential portions of it." - Rufus King, 1789
It is manifestly impossible for any sovereign to divest itself of a portion of its sovereignty, and remain a sovereign. It can lose a portion of its delegated powers; said powers having been delegated to it by the people, the real sovereign.
In any case, the State governments are not sovereigns, the people hold the sovereignty. The people created the State governments and delegated certain powers to the State government, just as they delegated certain powers to the Federal government.
The people as a political group making up a State are the sovereigns and have never ceded the slightest portion of their sovereignty.
If the State government is a sovereign and recognizes no higher power, how does the U.S. Supreme Court strike down State laws, or the Federal congress enact Federal laws that are binding on the States?
As the U.S. Supreme Court can strike down laws passed by Congress and Executive Orders of the President, the Federal Executive and Legislature are not sovereigns either. As the Congress created the Judicial branch, it is not a sovereign. The only Court congress can't abolish is the Supreme Court, however, Congress can strip the Supreme Court of appellate authority, leaving it with not much to do. And as the People can exercise their sovereignty to destroy all three Federal branches, and start over as with the Constitution, the whole Federal government is not sovereign. And the people of any State can rewrite their State constitution anew and destroy their existing government and replace it one more to their liking. It's good to be the sovereign.
The people can delegate their authority to declare war, establish organs or faculties of defence or offence, raise troops, equip vessels for war, or anything else that a sovereign has the power to do. The people can amend the current State or Federal constitution or write a new one.
The government, State or Federal, only has the powers that the people delegated to it, for the purpose of serving the people, as an agent of the people. The agent of the people, through a delegation of power from the people, does not become the sovereign master of the people. Not even a little bit.
After the 14th Amendment it is really hard to find State sovereignty. With that Amendment, the People dictated who is a citizen of a State. A State does not even enjoy self-determination regarding who its citizens are. All persons born, or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and the State wherein they reside. When a citizen moves from one State to another, and takes up residence in the new State, he becomes a citizen of the new State of residence. The State does not even have a say in the matter. The real sovereign has spoken.