I began with Jefferson Davis for the obvious reasons, but Davis, like Buchanan, did not throw in whole hog with the filibusters. He opposed Paulding’s arrest of Walker, but like Buchanan and Stephen Douglas preferred to legally buy new territory or seize it in a proper war rather than trusting to highwaymen on a geographic scale. Davis’s fellow Mississippian, Albert Gallatin Brown, did not have quite the same set of scruples. He rose after Davis to stake out a more extreme position:
If Walker has fitted out an expedition against Nicaragua, or any other country at peace with the United States, he has violated the law; but if he has girt his arms about him and voluntarily gone aboard a ship going to the coast of Nicaragua, avowing to all the world that he was going there to wage war against the Government, I hold he had the right to do so. In that there is no fitting out of an expedition. I hold it to be my right under the law, to-day, to take my musket upon my shoulder, go and tell the President and his Secretary of War, his district attorneys and his marshals, everywhere, that I mean, thus accoutered, to go and take part against Nicaragua, and they have no power to arrest me. If one has the right to go, two, three, four, five, or even five hundred have the right in the same manner, each going upon his individual account.
if you had a law to punish the intention to fit out an expedition beyond the limits of the Union, you might get hold of Walker -for that is all that he has done. He has gathered his material in New York, New Orleans, and Mobile, and perhaps other points; he has taken them man by man beyond the limits of the Union, and there fitted out his expedition, and gone to Nicaragua. In that, there has been no violation of law, because there is nothing in the law to punish the intention to fit out an expedition, if the expedition was fitted out beyond the Union.
With that formulation, one would have to work fairly hard to violate the Neutrality Act. Senator Brown couldn’t find it in himself to say where the line lay. Where did emigration end and fitting out an expedition begin? Davis at least hinted that a sufficiently large number of men might trip the law, even if that number had exceed that of most Army commands of the time. Brown countenanced at least as many as five hundred declaring that they would go abroad to filibuster and leaving together. Davis at least feigned ignorance; Brown embraced their purpose as their sacred right as American citizens.
Brown had a point too. While he and Davis certainly argued from political expediency, in the nineteenth century virtually no nation had any kind of permanent border controls to keep its populace in. Those largely developed during the First World War. If an American wanted to leave, gun in hand, he or she could do just that. The Texans had, after all. So had the Mormons. Once one crossed the border, one slipped the yoke of the nation’s laws. If nothing else, the filibusters sat comfortably within the American tradition of cavalier attitudes about the sovereignty of other countries and other people. The Cherokee could tell us that just as well as the Mexicans could and requiring Americans to abide by the same neutrality as their government certainly smells a bit like conscripting them, something which the nation had never done except in the Fugitive Slave Act.