The act of Captain Wilkes was denounced by the British Government, as an outrage upon British neutrality and a wanton trespass upon British sovereignty as represented by the Union Jack afloat over a British mail steamer. A demand was promptly made for the surrender of Mason and Slidell, and for an apology. There is no possible room for doubt that that demand was justified under the laws of nations and peculiarly so by the precedents of American contention, for it was in protest against precisely such sea seizures that this country had made war in 1812. But the people of the North were tremendously excited over an incident in which they greatly rejoiced, and it was in an extreme degree dangerous for the administration to contravene popular sentiment and to undo Captain Wilkes's work, by yielding to Britain's demands for the surrender of Mason and Slidell. From beginning to end of the war there was perhaps no problem so perplexing as that which this controversy presented to Mr. Lincoln's administration to solve. To refuse Britain's demands was to invite instant war with the greatest naval power in the world, with the certainty that France, already eager, would join forces with Great Britain in recognizing the Southern Confederacy and supporting it in its assertion of independence. In that case all that the United States had done toward the establishment of a blockade of Southern ports would have been quickly undone by the appearance of overmastering British and French fleets on the Southern coasts, and very probably by the landing of British and French forces to aid the Confederates in their war against the Union. For when war is on nations do not stop at technical interference. They are apt to furnish men and guns in aid of the cause they have espoused. In any case a declaration of war between Great Britain and the United States--a declaration of war which the capture of Mason and Slidell very narrowly threatened--would have resulted in the raising of the blockade of every Southern port and the opening of the South to that free traffic in arms, ammunition and supplies which chiefly the South needed in order to accomplish its purposes. Should the Government, on the other hand, yield to the British demand, it must encounter that highly inflamed popular sentiment which had compelled a congressional resolution of thanks to Captain Wilkes, and which--sanely or insanely--was disposed to twiddle its fingers at British or any other intervention in American affairs.