We have yet another interest still, and that no trivial one, in the republicanism of the state governments; an interest indicated, too, like the one last mentioned, in the very section in which this republicanism is assured. It relates to the defence against invasion. The general government is pledged to defend each of the states against invasion. Is it a thing of no moment, whether we have given such a pledge to free or to slave states? Is there no difference in the cost and hazard of defending one or the other? Is it of no consequence to the expense of life and money, involved in this undertaking, whether the people of the state invaded shall be united, as freemen naturally will be, as one man against the enemy? Or whether, as in slave states, half of them shall be burning to join the enemy, with the purpose of satisfying with blood the long account of wrong that shall have accrued against their oppressors? Did Massachusetts--who during the war of the revolution furnished more men for the common defence, than all the six southern states together--did she, immediately on the close of that war, pledge herself, as the slave holders would have it, that she would lavish her life in like manner again, for the defence of those whose wickedness and tyranny in peace should necessarily multiply their enemies and make them defenceless in war? If so, on what principle, or for what equivalent, did she do it? Did she not rather take care that the guaranty for a republican government should be inserted in the same paragraph with that for protection against invasion, in order that both the principle and the extent of the liability she incurred, might distinctly appear? The nation at large, then, as a political community under the constitution, have both interests and rights, and both of the most vital character, in the republicanism of each of the state governments. The guaranty given by the national constitution, securing such a government to each of the states, is therefore neither officious nor impertinent. On the contrary, this guaranty was a _sine qua non_ to any national contract of union; and the enforcement of it is equally indispensable, if not to the continuance of the union at all, certainly to its continuance on any terms that are either safe, honorable or equitable for the north. This guaranty, then, is not idle verbiage. It is full of meaning. And that meaning is not only fatal to slavery itself, but it is fatal also to all those pretences, constructions, surmises and implications, by which it is claimed that the national constitution sanctions, legalizes, or even tolerates slavery.