One thing that makes it very difficult for the Union (and rightly so) is that there just aren't enough competent generals at the beginning of the war. In my current game it's November 1861. Halleck and Fremont are beginning to make headway in Western Kentucky. McClellan has "liberated" Lexington, KY and is now on the move toward Bowling Green. All is well in the West.
The East, however, just got ugly. The Army of the Potomac is commanded by Nathaniel Banks and consists of three corps under Irvin McDowell, David Hunter, and Benjamin Butler. Butler, with the divisions of Hooker, Heintzelman, and Runyon (the latter being unattached), have feinted toward Fredericksburg in an attempt to either take that city or relieve pressure on my other two corps operating in the Harpers Ferry area.
Banks, with McDowell and Hunter (four divisions with a fifth division unattached), caught Stonewall Jackson with his corps inside Harpers. Jackson has made several attempts to break the siege with assistance from two other rebel forces under Joe Johnston and John Magruder. There were three assaults made against Banks, all of which were turned back with heavy casualties. Jackson, Johnston, and Magruder were now all inside the Harpers Ferry defenses licking their wounds.
With winter fast approaching, one breach already in the Harpers Ferry defenses, and my belief that Jackson had already been whipped, I elected to have Banks assault the works. On day four he did so. Bad idea. McDowell and Hunter were hurled back with upwards of 17,000 casualties. It was a disaster. Jackson, seeing that Banks was reeling, counterattacked successfully on day six, taking down an additional 6,000 federals and sending Banks running for Maryland.
After all was said and done, Banks's army was wrecked. Four of the five original divisions were decimated (literally). leure: To make things worse, Butler got into a nasty scrape in Fredericksburg and is now back in Manassas with 3,000 fewer troops.
The lesson learned is this:
1. Don't presume that your enemy is weak.
2. When choosing to assault enemy fortifications, do so with a commander with a better attack rating that Nathaniel Banks.
3. Pray that 1862 brings better generals.