Appendix 1. Texts of formal declarations of war by the United States.(Declarations of War and Authorizations for the Use of Military Force: Historical Background and Legal Implications)

War with Great Britain 1812

(Act of Jun. 18, 1812, ch. 102, 2 Stat 755)

CHAP. CII.--An Act declaring War between the United Kingdom of Great Britain and Ireland and the dependencies thereof, and the United States of America and their territories.

Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That war be and the same is hereby declared to exist between the United Kingdom of Great Britain and Ireland and the dependencies thereof, and the United States of America and their territories; and that the President of the United States is hereby authorized to use the whole land and naval force of the United States to carry the same into effect, and to issue to private armed vessels of the United States commissions or letters of marque and general reprisal, in such form as he shall think proper, and under the seal of the United States, against the vessels, goods, and effects of the government of the said United Kingdom of Great Britain and Ireland, and the subjects thereof.

APPROVED, June 18, 1812.

[Terminated by Treaty of Ghent, entered into force Feb. 17, 1815. 8 Stat. 218, Treaty Series 109.]

War with Mexico 1846

(Act of May 13, 1846, ch. 16, 9 Stat. 9)

CHAP. XVI.--An Act providing for the Prosecution of the existing War between the United States and the Republic of Mexico.

Whereas, by the act of the Republic of Mexico, a state of war exists between that Government and the United States:

Be it enacted by the Senate and House of Representatives of the United States of America in Congress assembled, That, for the purpose of enabling the government of the United States to prosecute said war to a speedy and successful termination, the President be, and he is hereby, authorized to employ the militia, naval, and military forces of the United States, and to call for and accept the services of any number of volunteers, not exceeding fifty thousand, who may offer their services, either as cavalry, artillery, infantry, or riflemen, to serve twelve months after they shall have arrived at the place of rendezvous, or to the end of the war, unless sooner discharged, according to the time for which they shall have been mustered into service; and that the sum of ten millions of dollars, out of any moneys in the treasury, or to come into the treasury, not otherwise appropriated, be, and the same is hereby, appropriated for the purpose of carrying the provisions of this act into effect.

SEC. 2. And be it further enacted, That the militia, when called into the service of the United States by virtue of this act, or any other act, may, if in the opinion of the President of the United States the public …