Nothing Civil about it

As an amateur historian, I have now had the opportunity to come face to face with the gaping holes in my familiarity with the Civil War, or the War of the Northern Aggression or the War of the Southern Rebellion depending upon your bent.
The chronological part is easy enough to grasp and I found a perfect book for that pursuit at Fredericksburg. It's Marina's questions, specifically "why?" and "how?" with which I struggle.
War inevitably leads to innovation, especially in artillery and repeating arms in the 1860s which far outstripped the progress in military tactics or medicine. More than half the casualties were from disease to say nothing of the lines of blue and grey that squared off in the face of each other and poured volleys of half inch hot lead balls across short distances.
Our battlefield visits have not been in chronological order, but it is enlightening to present them that way, at least the ones in Maryland and Virginia.

Let's start with First Manassas, or Bull Run. Learned that the CSA named battles for nearby towns while the Union tended to use streams or rivers.
While folks were attending church in Washington DC the Sunday morning of July 21, 1861, they thought they heard the rumble of distant thunder. When they learned it was the long anticipated first battle that many on each side assumed would be all that was necessary for victory they packed picnics and sat on adjacent hillsides to watch the show.
Green troops in each army got their first taste of battle. Union soldiers were even excited because their 90 day conscriptions were about to expire.
There's no way to condense the story on this single page, but as the monument's movie is entitled, it was The End of the Innocence and the beginnings of the grim reality of war for two determined adversaries.

The Henry Hill House which would be a focal point in both battles. Really illustrates the importance of high ground. 

Monument to TJ "Stonewall" Jackson who stood in the face of the Union like a, well, you get it.