Stated broadly, so as to acquire somewhat the force of a universal proposition, the principle of federalism is just this:—­that the people of a state shall have full and entire control of their own domestic affairs, which directly concern them only, and which they will naturally manage with more intelligence and with more zeal than any distant governing body could possibly exercise; but that, as regards matters of common concern between a group of states, a decision shall in every case be reached, not by brutal warfare or by weary diplomacy, but by the systematic legislation of a central government which represents both states and people, and whose decisions can always be enforced, if necessary, by the combined physical power of all the states.  This principle, in various practical applications, is so familiar to Americans to-day that we seldom pause to admire it, any more than we stop to admire the air which we breathe or the sun which gives us light and life.  Yet I believe that if no other political result than this could to-day be pointed out as coming from the colonization of America by Englishmen, we should still be justified in regarding that event as one of the most important in the history of mankind.  For obviously the principle of federalism, as thus broadly stated, contains within itself the seeds of permanent peace between nations; and to this glorious end I believe it will come in the fulness of time.

And now we may begin to see distinctly what it was that the American government fought for in the late civil war,—­a point which at the time was by no means clearly apprehended outside the United States.  We used to hear it often said, while that war was going on, that we were fighting not so much for the emancipation of the negro as for the maintenance of our federal union; and I well remember that to many who were burning to see our country purged of the folly and iniquity of negro slavery this used to seem like taking a low and unrighteous view of the case.  From the stand-point of universal history it was nevertheless the correct and proper view.  The emancipation of the negro, as an incidental result of the struggle, was a priceless gain which was greeted warmly by all right-minded people.  But deeper down than this question, far more subtly interwoven with the innermost fibres of our national well-being, far heavier laden too with weighty consequences for the future weal of all mankind, was the question whether this great pacific principle of union joined with independence should be overthrown by the first deep-seated social difficulty it had to encounter, or should stand as an example of priceless value to other ages and to other lands.  The solution was well worth the effort it cost.  There have been many useless wars, but this was not one of them, for more than most wars that have been, it was fought in the direct interest of peace, and the victory so dearly purchased and so humanely used was an earnest of future peace and happiness for the world.