The French and especially British navies wreak havoc with the Union navy unless you've been building up nearly from the start.
Unless the South is building up a navy--which it really can't afford and isn't historical--the Union doesn't really need any more steam or sailing frigates to do what it has to do. Transports I build to put into shipping for income and some brigs for scouting and sometimes to carry sundry small units to some part of the coast.
I have to say the only time I've ever had FI I triggered it with an event I wrote myself because the South was at their knees mid-63 and I didn't want to quit the game, so I gave the Confederacy 50 more NM and FI.
For a year the French and British navies ruled the waves, but since my armies were pretty much built up I could pull a couple of fat corps to put up into Norther New England and on the Canadian boarder making two new armies and increasing their sizes a little so that each had a corps of its own. The rest of my money went into building up the navy which took the better part of a year. But then the tides turned and Britain and France got clobbered badly.
I was a bit disappointed with the land situation. It was not much of a challenge. British troop quality is good and leadership is not bad, but they cannot create new corps and I have to question their strategy. They sent a fat corps of the BEF (British Expeditionary Force) on a march down from Moncton, New Brunswick to Bangor, Maine where they halted where I confronted them with one of my Northern armies. After some doing I drove them back from there. Bangor has no meaning strategically at all. I think sacking Boston would have been much better. They would have had a large harbor and it would have been costly for the Union as long as they held it, but Bangor???
Another smaller BEF corps dropped down from Montreal into New York State. It took Fort Montgomery and then Plattsburgh on the coast of Lake Champlain where I caught them and then drove them back. After some hard fighting I drove them off to the east and took Montreal and then Quebec.
One division sized force sent a brigade into Detroit and then Toledo. I could only counter with a couple of brigades at first, but then railed Rickets with his division and a second division under his command--because he has strategic 4 and can operate okay independently with 2 division--up from West Virgina up to Michigan and took back Toledo and Detroit and drove the Brits across the Detroit River to Amherstburg. I let one division guard Detroit while Ricket's divisions went up to Port Huron and across to drop down behind the Brits, where I eventually drove them out and back with some hard fighting. Then I send one small corps from Northern New York through Buffalo from the other direction and trapped them in London where they were besieged and wiped out.
When I started thinking about invading England I quit, because... well, it's not fantasy football you know

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