Klan members march in Washington, 1925 . (Library of Congress)

Among the few points of agreement among members of the two major political parties is that the Ku Klux Klan is bad. This has not always been an agreed-upon position — for years, the Klan actively endorsed political candidates — and it’s not a uniformly held position by everyone in either party. But as a general rule, the Klan is a mutually agreed-upon bad thing.

What that means, though, is that the Klan is also then used as a way of disparaging political opponents. For example, there’s this, retweeted by prominent conservative Dinesh D’Souza during President Trump’s speech on Tuesday night.

Sen. Ted Cruz (R-Tex.) declared his political opponents “the party of the Ku Klux Klan” last month. Cruz doesn’t mean that members of the Klan are all Democrats today, something that would be unexpected in part because the heavy concentration of black voters in the party. He meant that Democrats are responsible for the Klan, which is a well-worn trope on the right. Which is why he said it.

Virginia Commonwealth University created a map that shows the spread of the Klan during its resurgence a century ago. Here’s the spread of local Klan organizations from 1915 to 1940.

By 1920, the Klan had broken out of the Alabama-Georgia region into other Deep South states — and into Richmond. That’s a reminder of the real genesis of the Klan, half a century before VCU’s animation. It was born as a reaction to the Richmond-based Confederacy’s defeat in the Civil War and initially manifested as an effort to tamp down on the incipient political and social standing of freed black slaves.

It was, as Cruz and D’Souza will surely note, a Republican president — the first Republican president, Abraham Lincoln — who freed the slaves. The Emancipation Proclamation freed those held in bondage in Confederate states in 1863; the 13th Amendment, passed before but ratified after Lincoln’s death, eliminated slavery nationally. The first rift between the two parties was a rift that overlapped with views of slavery: the Republican/Union North and the Democratic/Confederate South.

Put another way: The people who started the Klan were probably Democrats, just as they were mostly Southerners. That’s the early Klan, that emerged during the Reconstruction period after the Civil War in Tennessee. The reemergent Klan of the 1910s was also started in the South, as the animation above indicates, and at the time, those states were still Democratic. It’s more fair to credit the geography with creating the Klan than it is the politics, since we can at least be certain of geographic origin. The political aims of the Klan overlapped with the political aims of Democrats after the war and a century ago, but there’s no indication that the party deliberately created the organization any more than there is an indication that Canada deliberately created Nickelback.

Better: It’s like blaming the Unabomber on the Montana Territory — pinning fault on a sort-of-recognizable but not-really-related thing that also doesn’t exist anymore. It’s critical to point out that talking about the Democratic Party of early 20th century Alabama is like talking about Alexander Graham Bell’s telephone in relation to the iPhone. It’s … not really the same thing.

Let’s look at presidential election results. Consider this metric of partisanship: how much more or less Republican a state voted than the country on the whole. So if New York backed the Democrat by 20 points but he won nationally by 10 points, New York is 10 points more Democratic than the country on the whole. Looking at elections since the Klan reemerged a century ago, the average margins by which Republican- and Democrat-preferring states deviated from the national results narrowed and then widened again.

(Note that spike on the Republican side in 1964; we’ll come back to it.)

Here’s something interesting, though. We can draw a line from the Democrats at the start of our graph through the most recent Republican results and get a fairly straight track.

Why? Because there’s a group of states that have helped dictate what these results look like. If we pull out the five states that constitute the Deep South — Alabama, Georgia, Louisiana, Mississippi and South Carolina — they track roughly along that dashed line.

Notice how much less volatile the early results among Democratic-voting states are when we set aside the Deep South. Those five states were very Democratic a century ago — and now they are not.

You can see here, too, that big spike in 1964, all a function of the Deep South. This graph compares results for the Democratic presidential candidate with those for the Republican. In 1964, those states were essentially the only ones (besides Republican candidate Barry Goldwater’s home state of Arizona) to vote against Lyndon Johnson. Why’d they vote against Johnson? In large part, because Johnson championed the 1964 Civil Rights Act.

As racial politics evolved between the Republican and Democratic parties nationally, the Deep South began moving more and more to the Republicans. In 1948, Strom Thurmond ran as a “Dixiecrat,” a pro-segregation Democrat from the South. He carried most of the Deep South (which is why the results between the major parties was closer in southern states that year). With the exception of Georgia native Jimmy Carter’s bids in 1976 and 1980 and the exception of 1968, when the Deep South backed the segregationist George Wallace over either major party candidate, the Deep South voted more Republican than the rest of the country in every election after 1964.

Something similar happens when we consider the partisanship of members of Congress. The VoteView project evaluating the partisanship of Congress over time allows us to create a similar picture of how the South moved from the Democratic to Republican parties.

Here’s the partisanship of each chamber of Congress since the outset of the Civil War. (Members of third parties are ignored.)

And here’s what happened once we extract the Deep South. Immediately after the war, the elected leadership of those states was Republican, but that shifted quickly as Southerners recoiled against Reconstruction policies (with the sympathies of Andrew Johnson, who succeeded Abraham Lincoln). The overall trend mirrors that above:

Those shifts — in presidential voting and on Capitol Hill — make clear that the Democratic south that was the birthplace of the Klan is not linked to the Democratic Party as it exists today. It’s a bit like a kid in college who dabbles in communism but who grows up to be a libertarian. Calling him a communist is awfully disingenuous.

But the point isn’t to make an historically valid point about the nature of racism. The point is to take one of the few things that everyone agrees is bad and using it to stamp your opponents any way you can.