When Polk could not acquire this desired territory by negotiation, he ordered General Taylor to enter the Rio Grande territory. This was done on January 13, 1846. On May 9, 1846, Polk notified the cabinet of his intention to recommend a war with Mexico within a few days, by which means he hoped to take the territory he could not buy. On the night of May 9, 1846, news came to President Polk that on April 24, 1846, the American army had had a skirmish with Mexican forces. On May 11, 1846, President Polk sent a message to Congress stating Mexico had "shed American blood upon American soil. War exists, and notwithstanding all our efforts to avoid it, exists by the act of Mexico herself." And two days later, May 13, 1846, President Polk informed his cabinet that the United States must acquire New Mexico, California, and the surrounding southwest territory as a result of the war. Some of the cabinet members wanted to take all of Mexico. Secretary of State Buchanan in a public letter said: "Destiny beckons us to hold and civilize Mexico." Americans had often tried to incite rebellions in Mexico. Many were arrested there and shot for treason. The United States, however, had never discouraged her citizens from trying to dismember Mexico. The circumstances surrounding the outbreak of hostilities between General Taylor and the Mexicans were these: President Polk had ordered General Taylor to enter the Rio Grande River region with American troops. He was arbitrarily accepting the Rio Grande and not the Nueces River as the southern boundary of Texas. The American troops marched down to the Rio Grande opposite Matamoras, a Mexican village south of the Rio Grande. They then blockaded the town and cut off its outlet down the Rio Grande. Mexicans crossed over the Rio Grande to drive the Americans away and to make them cease their interference with this Mexican village. Some Americans were killed in the skirmish. Rhodes on page 87, Vol. I, "History of the United States," says "Mexico was actually goaded on to the war."