If a President wants to acquire land/territory he may do so personally. This is his civilian right under Article 14, Citizen's Rights.
If the US government wishes to acquire land/territory, congress has authority to arrange this under Section 8, Powers of Congress, which includes powers
- To regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes;
- To declare War, grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water;
If new territory has been acquired and it is desirable to designate this as a new state of America, this matter must be conducted in accordance with
Article. IV. - The StatesSection 3 - New States"New States may be admitted by the Congress into this Union; but no new States 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."
So basically, ...
