It is obvious you need an education regarding how foreign territory can legally be added to the US; as both Hawaii and Texas have similar legal arguments, against the US empire.
US Constitutional law explicitly states that the annexation, of any legally recognized territory that is outside of the US, can only be made via Treaty, between both affected nation states. Both Texas and later Hawaii were annexed via a Congressional joint-resolution, which is in clear violation, of US Constitutional law, as any legislation enacted by Congress only has jurisdiction within the borders of the US.
The fact the illegal annexation of both Texas and Hawaii was allowed to take place, only reaffirms the degenerating of the American Republic to a US empire took place farther back than people realize, as evidenced by imperialists that infiltrated the American government, resulting in the long-term illegal occupations, of both nation states today.
This is technically incorrect. I used to use this same argument until I was educated recently.
There are historical precedents of states being admitted into the union without an official treaty of annexation, the most easily recognized being North Carolina by the federal government with no constitutional dispute.
While an official treaty of annexation between the Republic of Hawaii and the US was never ratified (one was signed by Mckinley in 1897 but failed in Congress), there really is no legal doctrine or requirement that such a treaty is necessary. In fact, Article IV, Section 3, Clause 1 of the US constitution specifically states that "New States may be admitted by the Congress into this Union; but no new State shall be formed or erected within the Jurisdiction of any other State; nor any State be formed by the Junction of two or more States, or Parts of States, without the Consent of the Legislatures of the States concerned as well as of the Congress.
Therefore, all that is technically needed for annexation is an official agreement between the governments of a nation desiring to be annexed and the US government, as well as an act of Congress approving said agreement. The Newlands Resolution served this purpose, acting an an official agreement (and therefore defacto treaty) between the Republic of Hawaii and the US (which was also in accordance with the RoH's own constitution and approved of by its government), and it was passed by simple majority in both houses, likely because they saw the benefit of having Hawai'i during the Spanish-American war.
This is why the "no treaty, no annexation" argument is weak at best, because technically the US does not have any additional criteria or legal precedent for a state to join the Union (besides what is covered in Article IV, Section 3, Clause 1 of the US constitution), nor did the US violate it's constitution or the constitutions of the Republics of Hawaii or Texas upon annexation.
The only real way for any state (to include Hawaii and Texas) to secede from the union would be either through successful armed rebellion against the US or through the Supreme Court overturning the ruling of White V. Texas (which states that the US is an indestructible union and cannot be dissolved) and/or Congress amending the constitution and implementing terms of secession for States wanting to separate from the US, as currently none exist.
Note: The most legitimate legal arguments and justifications for previous secessions (and some current efforts) were the ideas conveyed in the Declaration of Independence (...whenever any form of government becomes destructive of these ends, it is the right of the people to alter or to abolish it, and to institute new government...
) and the 10th amendment ("The powers not delegated to the United States by the Constitution, nor prohibited by it to the States, are reserved to the States respectively, or to the people"
, which in this case would apply to secession, as secession is not mentioned or detailed in the constitution), the ruling of White v. Texas clarified that neither the Declaration nor the 10th Amendment is legal justification for secession by any state.