Though strange to us it seemdAt first, that Angel should with Angel warr,And in fierce hosting meet, who wont to meetSo oft in Festivals of joy and loveUnanimous, as sons of one great SireHymning th' Eternal Father: but the shoutOf Battel now began, and rushing soundOf onset ended soon each milder thought.
—Paradise LostThe extremist has a problem: he is too extreme.
The word "extreme" is not used here as a pejorative; it simply describes the extremists' views in relation to the broader population from which he comes. His preferred solutions to the errors of the world lie far from the mean. He operates at the outer bounds of acceptable opinion. Perhaps he wants to declare independence from the British Empire; perhaps instead he wants to secede from the Union. There is a tactical symmetry that strings together extremist operations regardless of the particular ideology that motivates them. The legions of extremism include both the heroes and the villains of American history. This is where the leaders of Civil Rights Movement and the revolutionaries of '76 meet together with Confederate secessionists and 21st century terrorists.
|William Loyd Yancey|
Which is why victory through normal debate does not quite cut it. There is no time for slowly changing minds through rhetoric and reason. Radical actions is needed now—but who will do it?
That is the crux of the extremist's problem. Imagine a population distributed by their opinion on an issue of importance. Let 0 represent the worst possible outcome (from the extremist's view); 100 will represent the opposite extreme. At present only a small proportion of the populace is on-board with action in the 90-100 range. Most of those on the extremist's "side" dwell somewhere around the 50-70 range. For the extremist's dreams to move from hazy visions to realities made tangible these people must be moved from the center to the edge. They must be radicalized.
But how to do it?
What was once a buffet of every option between 0 and 100 must be narrowed to a binary. The radical knows the person whose preferences are at 65 will not ever be terribly pleased with option 100. However, that person will take option 100 over option 0 every time that choice is forced upon her. The extremist's aim is to force this choice on every one. He realizes that even the squishiest moderate will endorse unpalatable radicalism if he or she perceives it is a choice between that and defeat.
Thus the radical seeks a crisis where compromise is no longer possible. The easiest way for him to do this is to manipulate events so that the controversy is no longer about an issue but an identity. You can compromise on an issue. You cannot compromise on an identity. The radical wins when the question at issue is no longer "what should we do?" but "who do you stand with?"
A historical example is in order.
In 1963 Martin Luther King Jr. and the Southern Christian Leadership Conference had hit a wall. They were a few weeks into the Birmingham Campaign. Bull Connor, a sheriff infamous for his extreme pro-segregation positions, was the guy in charge of putting them down. However, though he was still in power he had just lost his re-election campaign. A more moderate segregationist had been elected instead. Most Birmingham whites and many of its blacks saw this as progress. It was lauded as a working compromise. Moreover, many prominent members of the black community, especially those with successful businesses, did not want the instability protests would bring and refused to support the movement. Those who did support the movement were quickly bled out by the financial toll of paying bail and other fines associated with the protests. King's own stint in jail seemed to drain the protest of its energy. Its supporters dwindled day by day. If the black community could not be convinced to come out in force, the campaign would fail.
James Bevel, one of King's associates, had a suggestion for what could be done to turn things around: Use the children. High schoolers did not have to worry about losing their jobs if arrested. They could not be bled dry. But there was a more important reason to put children on the front lines. Their presence would impose a binary.
Which is exactly what happened next.
The next day, more than a thousand children stayed out of school, gathering at the church to march. Bull Connor, hoping to abort the demonstrations before they began, brought out the city’s police dogs. He also ordered firefighters to turn their hoses on the youngsters. With 100 pounds of pressure per square inch, the water hit with enough force to rip the bark off trees. Children were knocked down by the streams, slammed into curbs and over parked cars. Several demonstrators were attacked by dogs.This was the standard strategy of the SCLC, SNCC, and the other major Civil Rights groups. They would purposefully create a social crisis in hope that the the authorities would over-react and crack down on the movement. This, in turn, would motivate black community members that were previously too afraid or too apathetic to stand up in opposition to come out. With the entire black community on their side, black leaders now had an effective tool for imposing costs on the segregationists.
As Connor lashed the demonstrators with water, black businessman A. G. Gaston, from his office across the street, was on the phone with attorney David Vann. Gaston “was expressing a great deal of resentment about King coming in and messing up things just when we [through the city government] were getting a new start,” Vann recalls. “And then he said to me, ‘But Lawyer Vann, they’ve turned the fire hoses on a black girl. They’re rolling that little girl right down the middle of the street. I can’t talk to you no more.’”
Vann would later say that it was then, when Connor’s troopers attacked the children, that “in the twinkling of an eye the whole black community instantaneously consolidated … behind Dr. King.”
The Civil Rights movement waged a non-violent struggle. Extremists are not always so fond of sit-ins and civil disobedience. Violence will accomplish the same ends, often more effectively. When people are dying, the question "Whose side are you on?" has great valence. As violence staggers through its vicious spirals, individuals are forced to choose a side or die. To play on Trotsky, you may not be interested in civil war, but it will find interest in you.
The Islamic State of Iraq and Syria has been very explicit in their endorsement of this strategy. Their enemies are the moderates who live in what they call the "gray zone" — the subsection of Muslims who embrace Western lifestyles and values while maintaining their claim to the Muslim faith. Here is how they described the purpose of their attacks in France in their propaganda journal Dabiq:
The Muslims in the West will quickly find themselves between one of two choices, they either apostatize and adopt the kufrī religion propagated by Bush, Obama, Blair, Cameron, Sarkozy, and Hollande in the name of Islam so as to live amongst the kuffār without hardship, or they perform hijrah to the Islamic State and thereby escape persecution from the crusader governments and citizens....
As the world progresses towards al-Malhamah al-Kubrā, the option to stand on the sidelines as a mere observer is being lost.
As those with hearts diseased by hypocrisy and bid’ah are driven towards the camp of kufr, those with a mustard seed of sincerity and Sunnah are driven towards the camp of īmān.
Muslims in the crusader countries will find themselves driven to abandon their homes for a place to live in the Khilāfah, as the crusaders increase persecution against Muslims living in Western lands so as to force them into a tolerable sect of apostasy in the name of “Islam” before forcing them into blatant Christianity and democracy.
...Eventually, the grayzone will become extinct and there will be no place for grayish calls and movements. There will only be the camp of īmān versus the camp of kufr. 
This is what so much terrorism is about—including when the terrorists are not aiming to immanetize the Salafi eschaton. The accelerationist terrorist in Christchurch outlined the same logic in his manifesto. He endorsed these principles for obvious reasons. Blood and bodies are an effective way to turn a contest over issues into a battle between group identities.
I will leave things here for now. The purpose of this post was to briefly outline an explanatory model with widespread application. This model is not my invention. The first (and still the best description) of extremist tactics I read was in William Freehling's two volume study The Road to Disunion.
Freehling's study began with an observation and then a question that follow naturally from it. Freehling's observation: even just a few months before war began, only the smallest part of American slave-power was enthralled with secessionist fever dreams. Recognizing that leads to his question: So how did secession ever happen? How could what he titles the "bare minority of a minority" lead the South headlong to war?
If you have gotten this far, you know the answer. Through clever maneuver, the fire-eaters staged one political crisis after another whose express purpose was to turn every question in national politics into a referendum on who stood with whom. Compromise was driven out. Southerners were forced to pick sides. What they wanted was eclipsed by who they were. What they were was Southerners. They chose the South. After four decades of struggle, deep South extremists finally had the manpower needed to build their utopia. The moderates had been manipulated into a binary that would deliver victory.
Yet that victory never came. Many reasons for this have been given. In Freehling's next book he offered another: about one in three southerners opposed the Confederacy. This was opposition acted on, not merely thought out. Entire southern states opted against secession, sending troops to fight for the Union. Anti-Confederate communities across the South gave active support to Union spies and later, invading Union forces. By forcing Southerners into an us-vs.-them binary, the fire-eating radicals made the Confederacy possible... at the cost of the Confederacy's later defeat.
That is the risk of extremist politics. If successful, the bid for binary can provide radicals with the support they need to sculpt societies as their nightmares demand. But if the new order advances too fast, if splitting citizens asunder smarts too sore, then the extremist risks shocking his natural supporters into the hands of his enemies.
If you fare as fascinated by the search for general models of political behavior as I am, you might also like the posts "Islamic Terrorism in Context," "Three Modes of Protest in American History," and "Chinese Are Partisan Too." To get updates on new posts published at the Scholar's Stage, you can join the Scholar's Stage mailing list, follow my twitter feed, or support my writing through Patreon. Your support makes this blog possible.
 Juan Williams, Eyes on the Prize: America's Civil Rights Years, 1954-1965, 2nd ed. (New York: Penguin Books, 2013), ch. 6.
 "The Extinction of the Greyzone," Dabiq iss 7, pp. 54-67. Archived here https://archive.is/VE0jj#selection-97.0-112.0, Accessed 26 August 2019.
 William Freehling. The Road to Disunion, vol I: Secessionists at Bay, 1776-1854. (New York: Oxford University Press, 1991); The Road to Disunion, vol II: Secessionists Triumphant, 1854-1860. (New York: Oxford University Press, 2007). Eric Foner's review of the series for the New York Times is also interesting.
 William Freehling, The South Against the South: How Anti-Confederate Southerners Shaped the Civil War (Oxford: Oxford University Press, 2002).