An oath is a legal contract. If a person takes an oath, then violates it, it is a breach of that contract.
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Now you are just being silly.
Ya think?
James Madison Federalist #43
The extent of this federal district is sufficiently circumscribed to satisfy every jealousy of an opposite nature And as it is to be appropriated to this use with the consent of the State ceding it; as the State will no doubt provide in the compact for the rights and the consent of the citizens inhabiting it; as the inhabitants will find sufficient inducements of interest to become willing parties to the cession; as they will have had their voice in the election of the government which is to exercise authority over them; as a municipal legislature for local purposes
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Samuel Adams to Elbridge Gerry 22 Aug. 1789
The Sovereignty of the State extends over every part of its Territory. The federal Constitution expresses the same Idea in Sec. 8, Art. 1. A Power is therein given to Congress "to exercise like Authority," that is to exercise exclusive Legislation in all Cases whatsoever, "over all places purchased by the Consent of the Legislature in which the same shall be, for the Erection of Forts, Magazines, and other needful Buildings," among which Light-houses may be included. Is it not the plain Conclusion from this Clause in the Compact, that Congress have not the Right to exercise exclusive Legislation in all Cases whatsoever, nor even to purchase or controul any part of the Territory within a State for the Erection of needful Buildings unless it has the Consent of its Legislature.
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Joseph Story, Commentaries on the Constitution 3:§§ 1212—22
§ 1214. Nor can the cession be justly an object of jealousy to any state; or in the slightest degree impair its sovereignty. The ceded district is of a very narrow extent; and it rests in the option of the state, whether it shall be made or not. There can be little doubt, that the inhabitants composing it would receive with thankfulness such a blessing, since their own importance would be thereby increased, their interests be subserved, and their rights be under the immediate protection of the representatives of the whole Union. It is not improbable, that an occurrence, at the very close of the revolutionary war, had a great effect in introducing this provision into the constitution.
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St. George Tucker, Blackstone's Commentaries 1:App. 276--78 1803
The exclusive right of legislation granted to congress by this clause of the constitution, is a power, probably, more extensive than it was in the contemplation of the framers of the constitution to grant: such, at least, was the construction which the convention of Virginia gave to it. They, therefore, proposed an article, as an amendment to the constitution, declaring, "that the powers granted by this clause, should extend only to such regulations as respect the police, and good government thereof." The states of New-York and North-Carolina proposed similar amendments; and one to the like effect was actually proposed in the senate of the United States, but shared the fate of many others, whose object was to limit the exercise of power in the federal government.
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FYI- 'federal' is not the same thing as 'national'. The Founders used the 2 different terms for a reason.
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When we accept the government can strip the rights of a citizen without due process
They do it all the time with less justification than this case has.