Today is Juneteenth. It commemorates the day in 1865 that the Emancipation Proclamation was finally put into effect in Texas and the last slaves of the fallen Confederacy were liberated by the Union Army.
The Civil War was mostly over by then. Robert E. Lee surrendered in April 1865. Jefferson Davis was captured in May 1865. But Texas was not complying with the Emancipation Proclamation. It took some encouragement from a bunch of guys in blue uniforms for Texas to finally do the right thing and let their slaves free.
The moral of the story is that even good laws require force to be upheld. Otherwise, they are only suggestions. So before you support a law, ask yourself if you would be willing to send a bunch of guys in blue uniforms to someone's house to enforce it.