James Buchanan citations

Speech to Congress (8 January 1861).
Contexte: It is said that serious apprehensions are to some extent entertained (in which I do not share) that the peace of this District may be disturbed before the 4th of March next. In any event, it will be my duty to preserve it, and this duty shall be performed.
In conclusion it may be permitted to me to remark that I have often warned my countrymen of the dangers which now surround us. This may be the last time I shall refer to the subject officially. I feel that my duty has been faithfully, though it may be imperfectly, performed, and, whatever the result may be, I shall carry to my grave the consciousness that I at least meant well for my country.

Speech before Congress (3 December 1860).
Contexte: The course of events is so rapidly hastening forward that the emergency may soon arise when you may be called upon to decide the momentous question whether you possess the power by force of arms to compel a State to remain in the Union. I should feel myself recreant to my duty were I not to express an opinion on this important subject.
The question fairly stated is, Has the Constitution delegated to Congress the power to coerce a State into submission which is attempting to withdraw or has actually withdrawn from the Confederacy? If answered in the affirmative, it must be on the principle that the power has been conferred upon Congress to declare and to make war against a State. After much serious reflection I have arrived at the conclusion that no such power has been delegated to Congress or to any other department of the Federal Government. It is manifest upon an inspection of the Constitution that this is not among the specific and enumerated powers granted to Congress, and it is equally apparent that its exercise is not "necessary and proper for carrying into execution" any one of these powers. So far from this power having been delegated to Congress, it was expressly refused by the Convention which framed the Constitution.

Speech before Congress (3 December 1860).
Contexte: The course of events is so rapidly hastening forward that the emergency may soon arise when you may be called upon to decide the momentous question whether you possess the power by force of arms to compel a State to remain in the Union. I should feel myself recreant to my duty were I not to express an opinion on this important subject.
The question fairly stated is, Has the Constitution delegated to Congress the power to coerce a State into submission which is attempting to withdraw or has actually withdrawn from the Confederacy? If answered in the affirmative, it must be on the principle that the power has been conferred upon Congress to declare and to make war against a State. After much serious reflection I have arrived at the conclusion that no such power has been delegated to Congress or to any other department of the Federal Government. It is manifest upon an inspection of the Constitution that this is not among the specific and enumerated powers granted to Congress, and it is equally apparent that its exercise is not "necessary and proper for carrying into execution" any one of these powers. So far from this power having been delegated to Congress, it was expressly refused by the Convention which framed the Constitution.

Responding to suggestions that he run for President in 1856, as quoted at wheatland.org http://www.wheatland.org.

As quoted in Presidential Leadership : Rating the Best and the Worst in the White House (2004) edited by James Taranto and Leonard Leo.

Inaugural address (4 March 1857).

Said to Abraham Lincoln on the ride back from Lincoln's inauguration as president (4 March 1861); as quoted in James Buchanan (2004) by Jean H. Baker, Pg 140; This or slightly paraphrased variants or abbreviated versions have also been been reported as having been said before the inauguration:
Sir, if you are as happy in entering the White House as I shall feel on returning [home], you are a happy man indeed.
If you are as happy entering the presidency as I am in leaving it, then you are truly a happy man.
As quoted in Presidential Leadership : Rating the Best and the Worst in the White House (2004) edited by James Taranto and Leonard Leo
Earlier variant: Some knave or fool got up a lie from the whole cloth and it was telegraphed over the country that I was about to purchase or had purchased a place somewhere else and would not return to Wheatland. If my successor should be as happy in entering the White House as I shall feel on returning to Wheatland he will indeed be a happy man. I am just now in my own mind chalking out the course of my last message. In it, should Providence continue his blessing, I shall have nothing to record but uninterrupted success for my country. The trouble about the slavery question would all have been avoided, had the Country submitted to the decision of the Supreme Court delivered two or three days after my inaugural.
Letter to William Carpenter (13 September 1860); as published in Historical Papers and Addresses of the Lancaster County Historical Society.

A statement he is reported to have made several times to others after the secession of South Carolina, or as early as after the election of Abraham Lincoln (1860), as quoted in Lincoln's War: The Untold Story of America's Greatest President as Commander in Chief (2004) by Geoffrey Perret.

As quoted in Presidential Leadership : Rating the Best and the Worst in the White House (2004) edited by James Taranto and Leonard Leo.