There are many who argued that Buchanan's actions as president made the Civil War inevitable. As we continue discussing the presidency in 2302, and soon discuss what makes for good and great presidents, we should also try to figure out what makes for bad ones.
From the NYT:
The question remains why such an experienced and intelligent president failed so miserably. Americans lavish attention on their successful presidents; yet there is much to be learned from our presidential failures. Buchanan did not suffer from feebleness or age or the insufficient powers of 19th century executives. Rather, he failed because he used that power with such partiality as an activist, ideologically driven executive. He had chosen sides in the great crisis and did not listen.
Negligent about slavery, but greatly attached to the values of white southerners, he went beyond political custom by castigating Republicans as disloyal. Yet his vision for the future of the United States was at odds with most Americans, whose definition of freedom did not include a slave republic dominated by a minority of slave owners. In one of the essential ingredients of successful leadership, Buchanan had failed to interpret his nation. Tragically, his administration served to encourage the future enemies of the republic as he gave the Confederate States of America precious time and support to organize for war.