Note 2 — IX THE UNITED STATES MEETS THE CRISIS May—July, 1846

Polk’s Message was based upon the view that the left bank of the Rio Grande belonged to the United States (p. 139), and this was said by some to be inconsistent with the idea (involved in the resolutions annexing Texas and in Slidell’s mission) that the boundary was an open question. But Polk’s language amounted only to an assertion of the American claim; and a claim, however just, may be a subject of negotiation. His expression (taken from the Washington Union of May 9), “shed American blood upon the American soil,” though denounced as a falsehood, was merely another assertion of the same claim, and was entirely in accord with the language of Madison, Jefferson, Monroe, Pinckney, and J. Q. Adams. A claimant, convinced that his cause is just, declares roundly, “This is mine,” even though aware that his contention is disputed. A more conservative statement would have been: Mexico has invaded a region that I hold to be ours, and shed American blood on what I regard as American soil; but Polk seems to have felt no doubts, and in a trumpet-call to arms qualifications would have appeared out of place.