Yah, personally I don't think either side ought be proud of a day so many Americans were killed or wounded in battle without a foreign enemy.
I feel like that. These kind of things are a never ending effort to make two wrongs make a right which never works.
The south was practicing slavery, which was legal at the time and has been practiced since the beginning of time and is still practiced today. The people of the "free and independent states" voted to secede over it and start their own country, likely also legal.
The north prosecuted an illegal war against the South to prevent secession.....later on adopted the guise of "ending slavery" which is little more than a cover up. But they won and history is written by the winners. So you have the Federal Behemoth of today which can cram things like sodomite marriage and gun control down the throats of the states. But "states rights" is not a panacea either. Not if you were a slave in the south prior to 1865 or if you are a guy who wants to legally carry a pistol in New York City or any number of other Yankee cities today. States can get things wrong too.
The real problem is mankind tends to gravitate toward tyranny for whatever reason.
