Excellent post. I always believed Buchanan was in a thoroughly unenviable position, and as such, couldn't get much done at all short of trying to keep the peace, something that just wasn't going to last. I read elsewhere that the Pennsylvanian Buchanan, who hailed from what I understood to be a fairly pro-abolitionist area, had his views shaped by whom many describe as his long-time lover, Senator and later Vice-President William Rufus de Vane King. King, an Alabaman (North Carolinian by birth), was strongly pro-slave. Their relationship was one of those badly-kept secrets (a la Strom Thurmond's half-African-American love child) in Washington circles in the 1830s-50s.

I read the textbook "Presidential Also-Rans" which attempted to analyze the losers in Presidential contests and how their potential administrations would've fared, and, alas, I've since forgotten what their conclusions regarding former California Senator Fremont were (Fremont himself just having come over from the Democrats, though at that time in CA, many prominent pols were Southern Democrats as opposed to those sympathetic to ending slavery, so I wasn't sure quite how committed he was to the abolitionist movement). I hope to purchase that book (I first got it at the library), and I highly recommend it.