Discarding that hypothesis, however, leaves us the important question, How did the idea of sending Taylor forward present itself to Polk? First, then, from his point of view it seemed entirely permissible. A proprietor is not debarred from going where a squatter has built a cabin; and in the light of our official claim and arguments Mexican occupation above the Rio Grande was merely by sufferance. The so-called "provocative act" of pointing guns at Matamoros could not be charged against the government, for Marcy had suggested other points also for Taylor's camp, leaving the choice to him. It was a defensive measure adopted by the General for military reasons in conjunction with pacific assurances and proposals; and we learn from Arista and others that it had a sedative effect on the property owners of that flimsily built city and on the army authorities.[7.27] No encroachment upon the powers of Congress appeared to be involved. Had Polk's aim been, as Calhoun alleged, to establish a boundary, he could not have tolerated Mexican posts, for the troops of foreign states cannot be permitted to sojourn within our officially defined limits. Besides, Polk had sent Slidell to treat on this very question, and Slidell had not given up the task. Though it rested with Congress to declare war, a President could legally, in the exercise of his discretion, take steps liable to bring about hostilities. Moreover Congress appeared to have authorized Taylor's movement. Corpus Christi, claimed by Tamaulipas, had been made an American port of delivery. A collection district had been established in the intermediate region. The declaration of Polk's Message, December, 1845, that our jurisdiction had been extended to the Rio Grande, and Marcy's appended report, which announced that Taylor's instructions were to regard that stream as our boundary, had raised no storm. For six months, admitted the chief Whig organ, our doings in this field not only had appeared to be endorsed by the people, but had gone on openly without calling forth "a single question from any public authority." Officially notified of the military occupation of Corpus Christi, Congress, instead of protesting, had voted supplies for the troops. Finally, Congress had instructed the Executive, in the resolutions for annexing Texas, to reach an agreement with Mexico regarding the boundary; it was his duty to persevere in the attempt until convinced he could not succeed; and Taylor's advance, as will presently be seen, appeared to him a proper step in the discharge of this obligation.[7.28]