Note 7 — IX THE UNITED STATES MEETS THE CRISIS May—July, 1846

One may also view the matter at a slightly different angle. It was possible for Mexico, on learning that General Taylor had advanced peaceably to the Rio Grande, to say, Very well, he may occupy the disputed district jointly with us for the present. England and the United States maintained a peaceable joint occupation of Oregon for years. Taylor’s advancing, therefore, did not per se and necessarily create a state of war. Now the United States did nothing else that could fairly be termed aggressive; but Mexico, by attacking American troops engaged in peaceful reconnoitring, destroyed the state of potential harmony, and consequently the state of war that ensued existed by her act. C. J. Ingersoll stated later (Cong. Globe, 29, 2, app., 125) that the language of the preamble was adopted for the purpose of conciliating, not offending, the Whigs; and one can see that it might seem likely to be easier for them to accept the war as an accomplished fact than to vote for a declaration.