Editor’s Note: The founder and Executive Chairman of KIND Snacks, Daniel Lubetzky is a social entrepreneur who founded and incubated non-profit organizations the OneVoice Movement, Empatico, and Frontline Impact Project to build bridges across lines of difference. The opinions expressed here are his own. Read more opinion at CNN.

CNN  — 

Extremism has a knack for metastasizing and coming back to wreak havoc upon its hosts. Once a cohort or society builds a hateful mindset, the hatred takes on a life of its own. Extremist ideology not only hurts a society’s enemies, but also eventually attacks from within and harms the society from which it originated. I first started observing this phenomenon abroad – and it saddens but does not surprise me that we are starting to see it haunt American democracy too.

Daniel Lubetzky

Consider how the kingdom of Saudi Arabia disseminated the Wahhabi sect’s fundamentalist attitudes against Jews and Christians at home and abroad. It helped to fund the madrassas that fostered the extreme perspectives that eventually contributed to the September 11th terror attacks on New York and Washington. Al Qaeda leader Osama Bin Laden did not just seek to destroy Americans – he wanted to destroy all things Western. The great irony is that his unbridled hatred had also prompted him to attack the Saudi kingdom, too. Bin Laden’s extremist hunger was such that even the Saudi Wahhabis who helped inculcate his all-consuming intolerance could no longer prove pious enough in his eyes. His efforts to overthrow the Saudi monarchy launched an opposition movement that got him expelled from the country.

In Israel too, the government has taken limited action to shut down the behavior of the so-called “hilltop youth,” extremist settlers who deem themselves highly religious despite not respecting the rabbis of the settlement. The lack of concerted effort to prevent and stop the group’s rock throwing and vandalism of Palestinian villages gave these fired-up youth permission to spiral out of control, eventually leading them to attack the Israeli army, too.

Or take the Beitar Jerusalem Israeli football club, notorious for its long history of not putting Arab players on the field. The club’s most fanatical supporters finally became so extreme in their intolerance that Beitar Jerusalem’s 2013 signing of two Russian League players who happened to be Muslim led to protests and anti-Arab chants against the very club that fueled the fans’ racist fire. Arsonists set fire to the club’s offices two days after the signing. More recently, some of the fans targeted a Christian player from Niger simply because his name, Ali Mohamed, sounded Muslim.

I recall a time in Germany, riding in a car with a German woman who was an authentic supporter of the OneVoice Movement I founded to foster Arab-Israeli understanding. She made a point of vehemently – and sincerely – condemning racism against Jews, but minutes later cursed out another driver and justified her tirade by casting slurs on Polish immigrants. She had superficially learned that the Holocaust was bad but had not internalized the dangers of bigotry against any group. If Polish people were not immune to her racism, to what other target would her hatred attach next?

While Germany has done a better job than many other nations to take concerted actions (like making Holocaust denial illegal) to discourage anti-Semitism, it is also experiencing a surge in neo-Nazism, particularly against Turkish immigrants. All nations are challenged to address the intolerant mindset at the root of racism; otherwise that intolerance eventually resurfaces and comes back to haunt us.

Here in the United States, there are Republican legislators and anchors on Fox News who have willingly participated in race-baiting and birtherism for years, even before President Trump hijacked the Republican Party. Republican Senate Majority Leader Mitch McConnell has looked the other way for close to five years as Trump incites violence and sows mistrust in our system. And Wednesday morning, rather than lead with truth, Senator Ted Cruz gave contorted explanations for why he – along with several other Republican senators and 121 House Representatives – would indulge Trump’s fabricated and fraudulent fantasies by objecting to certify the election results. Then came the insurrection. Mobs of Trump supporters, hopped up on Trump’s conspiracy theory of a stolen election and encouraged to go to the Capitol by the President himself, stormed and vandalized our nation’s Capitol building.

It was the disturbing culmination of a months-long series of attempts by Trump to bully state officials into “finding” votes that would help him win the 2020 presidential election, as almost all Republican “leaders” stood by with stunning silence – though elections officials in Georgia, headed by Secretary of State Brad Raffensperger, stood up for truth against pressure from Trump. To his credit, earlier on Wednesday, Mitch McConnell had sought to affirm that “the voters, the courts, and the States have all spoken” and that it was time for Trump to concede. But it was too little too late. McConnell himself stood by while the seeds of extremism were planted, leading to – in his words – “the unhinged crowd,” or, in other words, the domestic terrorists who came for him and his fellow legislators.

When thinking turns extreme, there is little room for nuance or aberration from the narrow mindset deemed acceptable. People become programmed to hear what they want to hear and tortured by cognitive dissonance when their own dogma does not stand to reason. When groups become so extreme in their thinking that they fail to realize the merits of an opinion from outside their “tribe” or when partisan fealty fuses into one’s identity, one’s values ultimately suffer.

Trump and a small subgroup of his most radicalized and violent supporters, who include White supremacists and Neo-Nazis, are responsible for this dark chapter. Nothing can justify their sedition. But beyond this specific situation, it would be simplistic to believe that extreme ways of thinking reside exclusively within the right. All extremes are bound together by their intolerance for “the other.” The far-left’s tendency to call others out and automatically cast judgment harms all of society by stifling the critical thinking, nuanced debate, and exchange of differing ideas that lead to progress – the very progress for which progressives advocate. If people feel “cancelled” or too intimidated to speak up, their repressed feelings are more likely to fester under the surface and emerge later in a more extreme form. The gap between both sides grows, leaving a vacuum of misunderstanding and division.

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    When terrorists or violent extremists cross the line, the only recourse is to forcefully stop them and prosecute them to the full extent of the law. For society at large, independent thinking and even avoiding partisan fanaticism can be antidotes to unruly tribalism in the future. Embracing the middle space characterized by critical thinking and nuance gives us a pathway for avoiding absolutist and hateful thinking that preys on societies from both the outside and within. While extremists are passionate, moderates overwhelmingly outnumber them. We can seize back the agenda for reason by recognizing our individual power and duty to stand up, particularly against the sort of violent extremism and domestic terrorism we witnessed in our nation’s capital.