In July 2005, while working as a foreign correspondent in London, I was alarmed to learn that two terrorists lived right down the street from me. The men had attempted to blow themselves up on the London transit system two weeks after the deadly “7/7” subway bombings that killed 52 commuters. Watching the failed suicide bombers being arrested at their apartment complex — stripped down to their underwear to ensure they weren’t wearing explosive vests — launched me on a reporting journey to answer a question: What had led these young men, living in Europe with Western freedom and opportunity, down the same path to terrorism I’d reported on so many times in the Middle East? In interviews with well-educated, often middle-class and seemingly moderate young men, I documented what was then the new and growing appeal in the West of Islamist violence built on false history and a deep, debilitating sense of victimhood.

Last month, I recognized many of the same forces driving my fellow Americans into extremism. I’m not equating the Jan. 6 rioters with those fighting to unite the world under a caliphate via a global campaign of terrorism. But domestic radicalism has deep parallels to jihadist terrorism: Both movements are driven by alienation from the political system and a resulting breakdown in social norms. For some groups and individuals, this breakdown leads to violence they see as justified to achieve political ends. Law enforcement officials are taking notice. The Department of Homeland Security now identifies American extremist violence, particularly among white-supremacist groups, as “the most persistent and lethal threat” on our shores. And, at least in recent years, violent acts by right-wing extremists have exceeded those of Islamist terrorists. Since 9/11, 114 people have been killed in attacks by right-wing terrorists in the United States vs. 107 by jihadist terrorists, according to data compiled by New America.

The similarities between domestic and Islamist terror groups are hard to avoid. Followers of both are drawn to a cause greater than themselves that gives them a shared identity and a mission to correct perceived wrongs, by whatever means necessary. At the core of this cause is a profound sense of victimization and humiliation. The terrorists I met from Afghanistan, Somalia, Saudi Arabia and West London all believed that their pride and purpose had been stolen from them — by, in their case, the United States and its allies — and so were drawn to a movement that promised to restore that pride and purpose, even by violence. Today’s American extremists think (because they’ve been told by the former president and other leaders) the system is rigged against them and is bent on dismantling everything they believe in.

For both groups, their sense of oppression is built on fantasy. I interviewed many Islamist terrorists with middle-class upbringings, steady jobs and graduate degrees. Among the rioters who assaulted the U.S. Capitol were doctors, business owners and real estate agents — more victors than victims of the system. “The militants often experience their humiliations vicariously — ‘our religion is supposedly under attack’ for the jihadis, ‘our race is purportedly under attack’ for the Proud Boys,” says Peter Bergen, who has written and reported on terrorism for more than 20 years. “It feeds into a sense of grievance that they then feel they need to act upon, even though it’s not like they themselves have suffered personally.”

Just as I had countless debates with Muslim extremists convinced that every event and institution (currency movements, the 2004 Iranian earthquake, the CIA, the United Nations) was diabolically conspiring against them, I now find myself having similar mind-numbing arguments with Americans about “deep state” plots, best exemplified by the “stolen” 2020 election and the Mueller investigation.

In both cases, adherents no longer believe that government or institutions will solve their problems. (Annual polling by Gallup shows that confidence in Congress, the presidency, the criminal justice system, newspaper and television news, banks, and big business is at or near historical lows.) So they feel compelled to take matters into their own hands, even by acts of violence. Invoking the spirit of the American Revolution, domestic extremists see themselves as performing their patriotic duty. Justice Department filings on several Capitol rioters noted their social media posts: “This is our 1776!” and “1776 has commenced.” When police searched the home of one of the rioters, they found not only weapons, but an American flag altered to add the slogan “Don’t Tread on Me” and signed by fellow members of the mob like a crude Declaration of Independence.

The U.S. is more politically polarized than ever. The Post’s Kate Woodsome asks experts what drives political sectarianism — and what we can do about it. (Kate Woodsome, Danielle Kunitz, Joy Yi/The Washington Post)

Similarly, during the “war on terror” in the Middle East, U.S. officials lamented the lack of public confidence in institutions and promised to fix them, in part to divert recruits away from extremism. Winning “hearts and minds,” they assured us, was as essential as winning gun battles. Who can claim that the U.S. political system is winning the hearts and minds of the American people today?

In July 2016, during a presidential campaign marked by Donald Trump’s already aggressive attacks on government, I asked then-Director of National Intelligence James Clapper if he ever applied the intelligence community’s metrics for failed states to the United States. “If you apply those same measures against us, we are starting to exhibit some of them, too,” he told me. “We pride ourselves on the institutions that have evolved over hundreds of years, and I do worry about the . . . fragility of those institutions.” He described “legal institutions, the rule of law, protection of citizens’ liberty, privacy” as “under assault.”

Five years later, Clapper tells me he sees those same trends worsening. “I wish it wasn’t true, but it is hard not to objectively observe those trends are continuing,” he said. “We have armed fanatic mobs attacking the seat of our democracy. This is what happens in unstable countries.”

The United States is not the Middle East, but Biden administration officials have told me they view the domestic terrorist threat with increasing alarm, particularly after the Capitol insurrection. Law enforcement officials worry that the Capitol assault was the beginning of a new phase of domestic terrorism, with extremists emboldened by the attack’s scale and impact. Yet, many GOP lawmakers are attempting to move on from Jan. 6, downplaying the threat the rioters posed to Congress or dismissing efforts to investigate the attack as detrimental to unity — a push that would be impossible to imagine in the wake of an Islamist terror attack on the homeland.

Trump was acquitted in the Senate, which his most hardcore supporters surely saw as a vindication of the riot, too. Trump himself was emboldened to interfere more, not less, in the political process after his first impeachment acquittal. It seems likely that America’s domestic terrorists will feel the same. “Hardcore extremists consider January 6 not a day of infamy but a day of victory,” says Sen. Sheldon Whitehouse (D-R.I.), who was at the Capitol at the time. In that belief, they have one more thing in common with those failed terrorists from my old neighborhood in London: Violence, for the most extreme and most lost among us, is both a means and an end in itself.

Twitter: @jimsciutto