US Presidency
1848

Whilst this territory was in our possession as conquerors, with a population hostile to the United States, which more than once broke out in open insurrection, it was our unquestionable duty to continue our military occupation of it until the conclusion of the war, and to establish over it a military government, necessary for our own security as well as for the protection of the conquered people. By the joint resolution of Congress of March 1, 1845, for annexing Texas to the United States, the adjustment of all questions of boundary which may arise with other governments was reserved to this Government. When the conquest of New Mexico was consummated by our arms, the question of boundary remained still unadjusted. Until the exchange of the ratifications of the late treaty, New Mexico never became an undisputed portion of the United States, and it would therefore have been premature to deliver over to Texas that portion of it on the east side of the Rio Grande, to which she asserted a claim.