Wow - seems like you had a lot of thought put into this. Is this from your 'Writing an alternative history with Fenian commerce raiders in 1867.'?
No just messing around this morning, although past research shaped it obviously. Other responses follow:
If the war was short and the Union won, why no 2nd term?
It was a negotiated peace after McClellan wins election. The war lingered in the south and west when the CSA would avoid engagement and retain mobility and over stretch Union logistics, then attack in the rear? S__t, I don't know.
Why would Northerners vote yes to a tax that is compensation to Southern slave holders?
End the draft, end an ugly lingering war (think of recent events). Progressiveness of the tax would be a populist theme (stick to the rich, including especially the propertied Southerners whose slave compensation would, of course, be taxed). Slow, decade-long emancipation that held Negroes in the agrarian South would reduce the immediate threat of black men as labor competition.
And what about a northern route from the Old Northwest to Puget Sound? Of which 3 ended up being built...
Sure, but the South lost the transcontinental railroad route after decades of locking it up. NW routes are an economic decision. A Southern Pacific route has other, more vital and immediate political benefits.
Why would this be a requirement for the South when it wasn't required in the North?
Because, just because. It's a negotiation after all. There needs to be greater commercial incentive and lower implementation costs for the railroad company, since the checkerboard of federal lands that they will receive won''t be anywhere near as arable and valuable as the UPRR/CPRR got.
But Indian cotton is something that the British can control, unlike Southern cotton.
Midlands industrialists like lower costs, and they like the quality of Southern cotton. Depends upon whether HMG would enact protectionist measures.
Have heard this type of comment before at varying times in history. This was stated when the HMS Dreadnought was commissioned in 1906. 1 ship does not an overpowering force make. Until there are enough vessels of this new type available to overpower all the remaining obsolete ships in formation, it can be defeated by sheer numbers of lesser weapon systems. Something about quantity having its own quality...and creating something that others can replicate just sets everyone's clock back to zero. At that point in time, building capacity becomes the deciding factor which the UK has a decided advantage.
A-yuh.
If the Confederacy was defeated, why would there be any need for 'quid pro quo'?
Remember, this was negotiated by McClellan, who got elected on a peace-at-any-price platform. This gambit combines a national political objective (seeing off the French) with an unacknowledged political leveling tool for the South.
Slave states? In an area that already outlawed slavery? There might be some pushback...
Of course NOT slave states! What did all those Union soldiers and sailors die for, just saving the Union?
Interesting. Why would we want Cuba? Is this to also placate Southern political interests?
Same reason as Mexico, only easier to implement quickly. Co-opt Cuban nationalism into a statehood movement.