WASHINGTON - Hours after President Donald Trump mused online about whether the Democratic lawmaker leading the impeachment inquiry should be “arrested for treason,” a 53-year-old mother of four in Wisconsin retweeted Trump’s post to her few hundred followers and added her own take.

"SHIFTY SHIFF NEEDS TO BE HUNG," wrote Jean Spanbauer, a onetime supporter of President Barack Obama. She had adopted Trump's epithet for Rep. Adam Schiff, D-Calif., slightly misspelling his name.

“As you can see, my tweets are pretty passionate,” Spanbauer, who uses a different name online, said in an interview, adding that she doesn’t specifically wish anyone physical harm. “It hits very close to home for me. What the Democrats are doing to our president, to the office and to the people of this country is disgusting.”

As Trump and his allies have aimed increasingly caustic language at Schiff in recent days, the attacks have been echoed by supporters on social media who often take the message a step further – invoking physical violence against one of the most prominent Democrats overseeing the inquiry that now threatens Trump’s presidency.

The chain reaction represents a new test of the power of weaponized language to inspire physical violence. Over the summer, Trump faced criticism for employing anti-immigrant rhetoric that was parroted by the man accused of fatally shooting 22 people at a Walmart in El Paso in August. In the fall of 2018, an avid Trump supporter mailed pipe bombs to prominent Democrats.

What many of the violent, anti-Schiff messages have in common is the inspiration they appear to draw from the president's words, or from the words of his associates and allies in Congress and conservative media.

A tweet from Rudy Giuliani, Trump's personal lawyer, arguing that Schiff should be "suspended" was reposted by a user with nearly 50,000 followers who envisioned the congressman's public hanging in a football stadium. The post remained live as of Sunday.

A tweet from Rep. Steve Scalise, R-La., describing Schiff as a "proven liar" who should be "held accountable" was reposted by a user with thousands of followers and a longing for the "good old days when traitors like Schiff would be hanged by the neck until dead." It also remained live.

A tweet from Matt Schlapp, the chairman of the American Conservative Union, was reposted by a user with only a small following who envisioned Schiff sitting in front of a firing squad. The post was taken down.

Neither Giuliani nor Schlapp responded to requests for comment. The White House also did not respond. But a spokeswoman for Scalise defended his rhetoric, saying the Louisiana congressman - among the victims of a shooting at congressional baseball practice in 2017 - knows firsthand the consequences of extreme language.

"As someone who was targeted by a leftist motivated by violent rhetoric towards Republicans, Whip Scalise is well aware of the dangers of that kind of rhetoric," said Lauren Fine, the spokeswoman. "Adam Schiff has a detailed history of using irresponsible, false and accusatory rhetoric throughout Trump's presidency, which is what this tweet simply documents in Schiff's own words."

A spokeswoman for Schiff said the security of the congressman and his staff is "always a top priority," declining to go into more detail about specific threats. A spokeswoman for the Capitol Police said authorities consult with individual congressional offices on "security-related matters" but declined to discuss precautions around the high-stakes impeachment inquiry.

The most graphic and specific threats against Schiff were quickly scrubbed from Twitter, whose policies prohibit threats of violence as well as the "glorification of violence." At least one additional tweet was removed after it was flagged for the company by The Washington Post.

But much of the vitriol remained. And the violent language also reached beyond Twitter, echoing on platforms such as Facebook and 4chan, a sprawling online agora where hate speech and violent threats are routine. A link to an article about Trump's accusation of treason against Schiff appearing on a Facebook page called "USA Patriots for Donald Trump," which boasts nearly 2 million followers, drew a slew of comments about the congressman being hanged.

The heightened focus on Schiff reflects the extent to which the former prosecutor and longtime Los Angeles-area congressman has become the bête noire of the Trump movement since becoming the de facto head of the investigation of Trump's efforts to enlist Ukraine's help in damaging former vice president Joe Biden, a Democratic presidential candidate. Schiff has come under fire from Trump and congressional Republicans as they seek to delegitimize the inquiry by portraying it as tainted by political bias. The nub of the criticism of Schiff is that he spoofed the president's call with his Ukrainian counterpart during a congressional hearing and that he made misleading statements about the nature of his prior knowledge of the initial whistleblower complaint.

Analysts say the pattern resulting in the violent rhetoric targeting Schiff makes evident the radicalizing effect of social media, which Trump uses to incite his followers against his perceived enemies.

Rep. Adam Schiff, D-Calif., Chairman of the House Intelligence Committee, center, leaves a meeting with House Speaker Nancy Pelosi of Calif., before a closed door caucus meeting about impeachment, Tuesday Sept. 24, 2019, on Capitol Hill in Washington. (AP Photo/Jacquelyn Martin)AP

"Whole online communities are forming around these sentiments, like MAGA," said Amarnath Amarasingam, an expert on political violence and an assistant professor at Queen's University in Kingston, Ontario. He referred to Trump's campaign slogan, "Make America Great Again."

"The online social movement of Trump supporters is very real, and a cohort of that movement has come out and said they're ready to take up arms when needed. This is something a few of us have been worried about for some time," Amarasingam said.

The internet is where the president's hold over his supporters comes into sharpest focus, the extremism researcher said: On Twitter, his opinions - and his disparaging views of other politicians - are received uncritically, giving Trump enormous power over his followers and "setting the stage for violence."

Some Trump critics have also used sharp language online, including accusing the president of treason and noting the maximum penalty.

"It's treason, pure and simple, and the penalty for treason under the U.S. code is death," former Massachusetts Gov. Bill Weld, who is challenging Trump for the Republican nomination, said last month on MSNBC of Trump's phone call with the Ukrainian president. The comment was tweeted by a reporter, and retweeted by Rep. Sheila Jackson Lee, D-Texas.

Former congresswoman Gabrielle Giffords, D-Ariz., who was shot in the head in a 2011 assassination attempt, said the responsibility of politicians to "seek the truth" and "treat their fellow Americans with respect" was heightened "in charged times."

Globally, public figures are not living up to that responsibility, said Jacob Davey, senior research manager at the Institute for Strategic Dialogue, a U.K.-based think tank dedicated to countering extremism and polarization. The result is increasing online radicalization - not just in the Middle East and Northern Africa, long the focus of extremism research, but also in the heart of the West.

Social media, he said, "has undoubtedly made engaging in such behavior easier than ever before, with users escaping the legal and social repercussions of their actions."

Trump's ability to craft an alternate universe for his supporters, in which he is the victim of lawless Democrats, rests on an unregulated online ecosystem, where fake news travels faster than the truth.

Spanbauer, who became dissatisfied with Obama during his first term and voted for his Republican challenger in 2012, said she gets most of her news on Twitter and YouTube. Among those she trusts are Fox News Channel host Sean Hannity ("of course") and Tom Fitton, the president of Judicial Watch ("thank God for Tom Fitton").

Trump, she said, channels her anger at Washington, while speaking directly to his supporters. "It's wonderful, really, what Trump does on Twitter," said Spanbauer, who has worked in retail and sales and struggles, along with her husband, to stay above the federal poverty line.

Beneath her verdict on Schiff's fate, which she acknowledges was hyperbolic, lies a firm conviction that the congressman is guilty of treason.

The impeachment inquiry, she said, is a "supreme insult to our country." Those leading it "should be held accountable to the length of the law," she added. "It's treason. It's treason."

Trump did not err in asking Ukraine’s president to investigate Biden and his son, in her view. “In fact, I’m so proud of him that he did it, that he asked them to look into the corruption that was going on,” she said, adding, “I back my president.”

Isaac Stanley-Becker of The Washington Post wrote this story.