=377. The Issues Involved.=—As a Mexican state, Texas had extended on the south and west to the river Nueces; but her inhabitants and the United States insisted on holding to boundaries based on the Louisiana Purchase and on claiming the “country between the Nueces and the Rio Grande.” The Mexicans resisted this claim; and when Polk ordered General Taylor to cross the Nueces, and later to advance to the Rio Grande, they attacked and defeated a small body of the American troops (April 24, 1846). Polk at once sent a message to Congress, in which he declared that war existed, “through the act of Mexico herself.” This statement was, on the whole, unwarranted, although a technical defense was easily made for it. It was really a case of a strong nation’s bullying a weak one; and, as we have seen (§ 353), the bullying had begun under Jackson and had been steadily carried on. But Congress, and a considerable portion of the people, especially in the South, accepted Polk’s proposition, and the war was effectively prosecuted. Its results were probably beneficial, in the main, since the territory was sure to become American some day; but its origin is not a pleasant topic for the patriotic American to dwell upon. Nor is it by any means certain that the Civil War was not in large part precipitated by that against Mexico. The latter contest gave the South a taste for fighting that was not altogether a warrant for the future calm of that section; and the additional territory acquired by the Union opened a new and disastrous phase of the slavery question (§§ 388, 411). [Illustration: JAMES K. POLK.]