So horrifically understandable

What seemed so clear to me is the cause/effect sequencing of the entire, awful story--how this led to that and that led to this and so forth and so forth and so forth, an almost inexorable chain of events. 

Begin here. I have no desire to be unkind to Oklahomans, but what needs to be said is that its white founding fathers were not of New England Puritan stock. Many of its pioneers were the stuff of Western legend, and Oklahoma itself, once called Indian Territory, was home to more than its share of tough hombres.

After the war, scores of ex-slaves left the cotton-picking south following the dreams of the West, just thousands of others up north. In Oklahoma, those emigres were Southerners especially, many of whom had never touted Abraham Lincoln, considered his "emancipation" talk astutely unnatural because it was clear to them that Lincoln had never had to live with. . .well you know, the n-word. 

By 1890, the Five Civilized Tribes who'd suffered through the Trail of Tears assessed their plight in Indian Territory and signed on to the provisions of the Dawes Act (1887), which offered land ownership to Native people if they would give up their tribal governance and associations. The effect, in Oklahoma as elsewhere, was to free up land for thousands more white pioneers, many of whom were embittered Southerners not so much leaving Dixie behind as lugging their losses and grievances with them.

Thus, while freed slaves moving into the region expected self-governance--freedom itself, in Indian Territory--the movers and shakers in city hall were, often as not, ex-Rebs who were not particularly interested the freedom of ex-slaves or "equality" (whatever that meant!) for, well, the n-word once again.

What's perfectly understandable is that, thus, a town like Tulsa, before the oil strikes, was the very model of segregation in the late 19th century, maybe not as blatant as it was in the Jim Crow South, but a world as segregated as any devised by apartheid South Africans. There was Tulsa--the white world--and there was Greenwood--the black. It was very simple and very clearly drawn.

Segregation or not, those ex-slaves not only survived, they flourished. Right there on the streets of Greenwood, their city, they did well, did better than well, in fact, so much so that some people called the place Black Wall Street.  

Then something happened. Exactly what, no one knows.

For a moment in time, old South-level hate threatened the barriers already set between the races in Tulsa--to white folks, what a black boy did to a white girl was an abomination that often led to lynchings throughout the South. Furthermore, the lynching of a white man had occurred recently, an event at which the Sheriff and the police chief had condemned the mob violence but made it clear that the hanging had been a benefit to life in the city.

It all seems so perfectly understandable. Thus, when crowds of white men, 2000 strong, were milling around the courthouse where the "Diamond Dick" Rowland, the kid who touched the white girl was held, dozens of African-Americans in Greenwood, some of them vets who'd only recently returned from the Great War, determined that what seemed inevitable was, this time, not going to happen. They went, single-file, to the courthouse and offered their protection to the Sheriff, who just waved them off. 

Tulsa had become a tinderbox. Then, on May 31, at 10:30 at night, a white man attempted to disarm an African-American World War I vet. A shot rang out. Thus it began. 

It was all so clearly a matter of this cause and that effect, that cause and this effect--it was so perfectly understandable. 

And so horribly evil.