I'll probably only do this once, since I don't like it when others do this sort of point-by-point debate, but you definitely know stuff, so...
Did they? I'd offer the 1st South African War, 1880-81, in evidence, counselor. Majuba as Exhibit A. I won't even mention Isandlwana...
It's a bit unfair to look at the performance of an army 20+ years after the Crimean War and argue that from that, the Crimean War Generation learnt nothing from their experience. It's like saying that because the US got bloody noses in Vietnam and they did so again in Iraq, nobody learnt anything from Vietnam.
There's a lot of the US in 1859 the British Army will be more than welcome to flounder around in; the reality is there (as always) are lakes and rivers to control and cities to defend, namely the maritime approaches to the Big 3; even the Chesapeake is secondary, as are the whole of the south Atlantic, Gulf, and Pacific - closer to tertiary.
That's true, and I don't claim to know what needs to be defended. But it's not reasonable to expect the British, who well know that without going on the offensive Canada is not defensible, would just sit back and get bogged down into lake and river defence (and even if it were so, the result is to get more ships to do the job, not sit passively). It's not like they haven't done this sort of grand raid before - they did it in China, they *tried to do* it in Crimea, and they can probably do it (with more ships) in America.
Winter comes earlier to the Saint Lawrence than anywhere else in North America worth bothering with in 1859; if the river is closed, Upper Canada (Canada West) and the important parts of Lower Canada (Canada East), meaning Montreal and the Eastern Townships are in US hands before the thaw. Given that this is two decades after the events of 1837-38, and a decade after both the provincial parliament was burned and the annexation manifesto was published, I'd expect the Americans would have been welcomed by more than a few of the Queen's subjects.
That's what the Fenians thought in OTL 1866, and it didn't work out. In any case, a US strategy that depends on a) the St. Lawrence freezing over completely and b) a hastily assembled US army capturing forts and seizing all strategic points of note (when they rarely did that on home soil during the ACW) before organized resistance comes from the UK is probably a risky strategy, especially if you give the few months needed for the US to prepare for what is, in essence, an unplanned conflict for both sides.
Actually, no; Scott's the man in charge, and he has fought and beaten the British before. Delafield, Mordecai, and (former) Captain McClellan, however, got to see the British at their finest in 1854-55. And Alfred Mordechai has no reason to resign - neither do Lee, the Johnstons, etc., and there are plenty of others likely to "rally."
Scott's an old-timer used to old war (in any case, too ill for command). Delafield will probably have to stay and look after coastal defences, and I'm not sure an armaments man like Mordecai wouldn't be staying at Washington. If the railroads are so important as many here claim, then railroad VP McClellan's expertise makes him the natural. I concede that Lee being made head is certainly a possibility, though again this raises questions about whether Lee was a good or a fortunate general (I lean towards the former).
US strategy is simple; defend the (major) ports, commerce raid the British, control the rivers and lakes, and invade the Province of Canada and New Brunswick with the largest armies as yet mobilized on the North American continent. Third time's the charm.
War in an election year is bad because you simply can't let bad things happen to your constituents. Oh, you're just going to sit back and watch our minor port burn, huh? I guess we'll just choose our own candidate/vote Lincoln/vote Breckinridge instead. Like the early CSA, the US is just politically incentivized to spread itself thin to give some semblance of Federal protection, no matter how strategically stupid that is.
From the "true southron's" point of view, perhaps; from the vast majority of southern whites, probably not. Manifest Destiny was widely supported north and south in the mid-Nineteenth Century, and if anything, new free states in the north implies some adjustments in existing slave territory. There's always the Texas 5-way split, for example.
How many Congressmen were 'true southerners' one can only guess, though an awful lot of the political elite were happy to break with the Union when secession came in OTL 1860. I'm not sure that the Texas 5-way split is a solution, because if it was then why didn't Congress do it at any point before 1860?
Palmerston was born in 1784 and died (historically) in 1865; Buchanan was born in 1791 and died in 1868. Neither one is exactly hale and hearty, despite the "Lord Cupid" element of Pam's career.
I meant in political terms: Buchanan is not personally/situationally in the best position to give direction to the war effort, which means that the North/South dispute in Congress will lead Union efforts astray; Palmerston doesn't have this problem (plus he was in pretty good health until he croaked).
Thanks for the agreement, but - 5 years?
Across Five Aprils would be four years, true?
True.