Sadly, the idea that “the arc of history bends toward justice” is not true. It’s a Hegelian myth that led ultimately to Nazi Germany, not to Juneteenth. Human nature does not improve, as we see in the descent of the first family from declaring independence from God and then fratricide.
In a fallen world, those subjected to injustice have to oppose that injustice until the Law above all laws is honored. That takes time.
Two years after President Lincoln issued the Emancipation Proclamation, the enslaved were still in chains in Texas. Leading a growing throng to the “Negro Church,” General Gordon Granger of the Union Army delivered General Order No. 3 at Galveston:
The people of Texas are informed that, in accordance with a proclamation from the Executive of the United States, all slaves are free. This involves an absolute equality of personal rights and rights of property between former masters and slaves, and the connection heretofore existing between them becomes that between employer and hired labor.
“Absolute equality of personal rights and property rights between former masters and slaves”: A great idea, not quite realized in the North or the South, the West or the East, even to this day. But at least it’s a great idea: better to fail, even miserably, at living up to an ideal than to not have it in the first place.
So instead of assuming that humanity is getting better and better, learning from its lessons of hatred and subjugation, let us be glad that God’s common grace continues to keep things from being as bad as they could be if we were left on our own. Juneteenth is a great time to thank the Lord for that.