Replying next day to a committee of notification, he said in part:
"I will neither conceal my gratification nor restrain the expression of my gratitude that the Union people, through their convention, in the continued effort to save and advance the nation, have deemed me not unworthy to remain in my present position. I know no reason to doubt that I shall accept the nomination tendered and yet, perhaps I should not declare definitely before reading and considering what is called the platform. I will say now, however, I approve the declaration in favor of so amending the Constitution as to prohibit slavery throughout the nation. When the people in revolt, with a hundred days of explicit notice that they could within those days resume their allegiance without the overthrow of their institutions, and that they could not resume it afterward, elected to stand out, such amendment to the Constitution as is now proposed became a fitting and necessary conclusion to the final success of the Union cause.... In the joint names of Liberty and Union, let us labor to give it legal form and practical effect."
In his letter of June 29, formally accepting the nomination, the President observed the same wise rule of brevity which he had followed four years before. He made but one specific reference to any subject of discussion. While he accepted the convention's resolution reaffirming the Monroe Doctrine, he gave the convention and the country distinctly to understand that he stood by the action already adopted by himself and the Secretary of State. He said:
"There might be misunderstanding were I not to say that the position of the government in relation to the action of France in Mexico, as assumed through the State Department and approved and indorsed by the convention among the measures and acts of the Executive will be faithfully maintained so long as the state of facts shall leave that position pertinent and applicable."
This resolution, which was, in truth, a more vigorous assertion of the Monroe Doctrine than the author of that famous tenet ever dreamed of making, had been introduced in the convention by the radicals as a covert censure of Mr. Lincoln's attitude toward the French invasion of our sister republic; but through skilful wording of the platform had been turned by his friends into an indorsement of the administration.
And, indeed, this was most just, since from the beginning President Lincoln and Mr. Seward had done all in their power to discourage the presence of foreign troops on Mexican territory. When a joint expedition by England, France, and Spain had been agreed upon to seize certain Mexican ports in default of a money indemnity demanded by those countries for outrages against their subjects, England had invited the United States to be a party to the convention. Instead, Mr. Lincoln and Mr. Seward attempted to aid Mexico with a sufficient sum to meet these demands, and notified Great Britain of their intention to do so, and the motives which prompted them. The friendly assistance came to naught; but as the three powers vigorously disclaimed any designs against Mexico's territory or her form of government, the United States saw no necessity for further action, beyond a clear definition of its own attitude for the benefit of all the parties.
This it continued to repeat after England withdrew from the expedition, and Spain, soon recalling her troops, left Napoleon III to set the Archduke Maximilian on his shadowy throne, and to develop in the heart of America his scheme of an empire friendly to the South. At the moment the government was unable to do more, though recognizing the veiled hostility of Europe which thus manifested itself in a movement on what may be called the right flank of the republic. While giving utterance to no expressions of indignation at the aggressions, or of gratification at disaster which met the aggressor, the President and Mr. Seward continued to assert, at every proper opportunity the adherence of the American government to its traditional policy of discouraging European intervention in the affairs of the New World.