Please tell me where it says that in the Constitution.
Article III, section 3, clauses 1 and 2 specifically speaks to how those citizens enraged in treason against the US should be handled and it’s through a legal process. Here is what it says:
Treason against the United States, shall consist only in levying war against them, or in adhering to their enemies, giving them aid and comfort. No person shall be convicted of treason unless on the testimony of two witnesses to the same overt act, or on confession in open court.
The Congress shall have power to declare the punishment of treason, but no attainder of treason shall work corruption of blood, or forfeiture except during the life of the person attainted.
Engaged in treason that is.
Article. I. Section. 8. The Congress shall have Power...To define and punish Piracies and Felonies committed on
the high Seas, and Offences against the Law of Nations; To declare War, grant Letters of Marque and Reprisal, and make Rules concerning Captures on Land and Water;...To make Rules for the Government and Regulation of the land and naval Forces; To provide for calling forth the Militia to execute the Laws of the Union, suppress Insurrections and repel Invasions; To provide for organizing, arming, and disciplining, the Militia, and for governing such Part of them as may be employed in the Service of the United States, reserving to the States respectively, the Appointment of the Officers, and the Authority of training the Militia according to the discipline prescribed by Congress;...To make all Laws which shall be necessary and proper for carrying into Execution the foregoing Powers and all other Powers vested by this Constitution in the Government of the United States, or in any Department or Officer thereof..... The Privilege of the Writ of Habeas Corpus shall not be suspended, unless when in Cases or Rebellion or Invasion the public Safety may require it.
Article. II. Section. 2. The President shall be Commander in Chief of the Army and Navy of the United States, and of the Militia of the several States, when called into the actual Service of the United States;....
Note: the offense of treason is apart from the laws of war and the laws of nations.