Douglas was by nature aggressive.

Determined to hold his Northern followers in the new issues which had grown out of his Freeport doctrine, and the new antagonisms which the recent slave code debate in the Senate revealed, he wrote and published in "Harper's Magazine" for September, 1859, a political article beginning with the assertion that "Under our complex system of government it is the first duty of American statesmen to mark distinctly the dividing-line between Federal and Local authority." Quoting both the paragraph of Lincoln's Springfield speech declaring that "a house divided against itself cannot stand," and the paragraph from Seward's Rochester speech, announcing the "irrepressible conflict," Douglas made a long historical examination of his own theory of "non-intervention" and "popular sovereignty," and built up an elaborate argument to sustain his course.

The novelty of this appeal to the public occasioned general interest and varied comment, and the expedient seemed so ingenious as to excite the envy of Administration Democrats.

Accordingly, Attorney-General Black, of President Buchanan's Cabinet, at "the request of friends," wrote, printed, and circulated an anonymous pamphlet in answer, in which he admitted that Douglas was "not the man to be treated with a disdainful silence," but characterized the "Harper" essay as "an unsuccessful effort at legal precision; like the writing of a judge who is trying in vain to give good reasons for a wrong decision on a question of law which he has not quite mastered." Douglas, in a speech at Wooster, Ohio, criticized this performance of Black's.

Reply and rejoinder on both sides followed in due time; and this war of pamphlets was one of the prominent political incidents of the year.
Thus Lincoln's advent in the Ohio campaign attracted much more than usual notice.