Confederate soldiers fighting for rich people's right to own slaves is very typical of warfare. Most wars are fought by poor men dying for rich people's causes.

This has to be the most ridiculous argument made by history revisionists. "Most Confederate soldiers couldn't afford a slave, so why would they fight if the war was over slavery!?!?!111!?!one!!!"

Guess what guys. Poor peasants being sent to war to defend a prince's claim to a throne didn't get to be kings after the war either. They got to go back home after the war and be poor.

American servicemen didn't come home to oil riches after the wars in the middle east.

This has been talked about throughout history. You can go back to ancient greece and find poems complaining about dying in a rich man's war. Shit, Goeing talked about this same fact in his trial:

“Why, of course, the people don’t want war,” Goering shrugged. “Why would some poor slob on a farm want to risk his life in a war when the best that he can get out of it is to come back to his farm in one piece. Naturally, the common people don’t want war; neither in Russia nor in England nor in America, nor for that matter in Germany. That is understood."

It's unbelievable that suddenly, and only for this war, the average soldier would have to have a stake in it to fight.

Quite the opposite of having no stake like a typical war, Confederate Soldiers had MORE stake to defend slavery than the average man pushed into service. This is coming from the American Civil War Museum:

Focusing on rates of slaveholding distracts from the ways that antebellum white Southerners understood slavery and participated in the slave economy and culture. Any white southerner could be a temporary master though slave hiring, could evangelize a proslavery Christianity, or imagine a national economy based on bound labor.

One did not need to own slaves to commit to the broad Confederate national vision that was based on slavery, or to fear the outcome of slavery’s destruction. In fact, proslavery ideology had implications for every white Southerner—as theorists consistently and loudly proclaimed that abolition of slavery would unleash a cataclysm of rape and murder. When Confederates rallied to repel “abolition armies” and protect their families, they did so because they anticipated that outcome.

Confederate soldiers rarely expressed a pure proslavery ideology in letters and diaries. (To paraphrase James McPherson, they felt no need to state the obvious.) Most often, they used popular shorthand like Yankee “fanatics,” or “our domestic relations,” hinting at how slavery fit into larger worldviews more readily understood. Few, if any, expressed skepticism about slavery in direct or indirect terms, and consistently defined the enemy as “abolitionists.”

Historian Joseph Glatthaar’s statistical analysis of the 1861 volunteers in what would become the Army of Northern Virginia reveals that one in 10 owned a slave and that one in four lived with parents who were slave-owners. Both exceeded ratios in the general population, in which one in 20 owned a slave and one in five lived in a slaveholding household. “Thus,” Glatthaar notes, “volunteers in 1861 were 42 percent more likely to own slaves themselves or to live with family members who owned slaves than the general population.” In short, Confederate volunteers actually owned more slaves than the general population.  

In fact, non-slaveholding soldiers from regions with fewer African Americans likely received greater exposure to slavery for having joined the army. The military regularly used slaves and implemented proslavery policies. The army conscripted slave labor on a massive scale for transportation, and in construction of military defenses. It also captured and returned to slavery thousands of escaped and free black men and women. Soldiers acted on fears of “servile insurrection” when they summarily murdered United States Colored Troops at Fort Pillow and the Battle of the Crater.

I'd like to end on a different note

I do think that there is an argument for confederate soldiers to support slavery, and not be horrible people because it was a norm of their time. We are all products of our time, so it's hard to hold them accountable for their mentality.

However, there is no similar excuse for Americans living right now to support a proslavery nation like the Confederacy. The current people who support The Confederacy don't have the excuse of their time. The current Americans who still support a slave nation are disgusting, and don't deserve to call themselves Americans.