If Marjorie Taylor Greene isn't beyond the pale, who is?

How far is too far? This is the question Republican leaders are being forced to grapple with as the public outcry grows over one of their newest House members, Marjorie Taylor Greene.

The Georgia freshman is best known for endorsing QAnon, the right-wing movement convinced of the fiction that Donald Trump is a messiah sent to defeat a cabal of Satan-worshiping, child-abusing, deep-state villains. But this is just one of the bizarre lies she has peddled. Her greatest hits include promoting the conspiracy theory that blames the 2018 Camp Fire wildfire in California on a space laser controlled by a prominent Jewish banking family, suggesting the Obama administration used its MS-13 "henchmen" to murder a Democratic National Committee staff member and floating the idea that the Clintons had John F. Kennedy Jr. killed. She has dabbled in 9/11 Trutherism and contended that various school shootings were false-flag operations. She also traffics in racist, anti-Semitic and anti-Muslim talk.

Greene does not draw the line at promoting bigotry and disinformation. Videos and social media posts from before she ran for Congress show her endorsing violence against those she sees as enemy combatants in an ongoing civil war. She has expressed support of social media calls to execute high-profile Democrats, including the House speaker, Nancy Pelosi, and FBI agents. When asked about such activities, Greene has dodged, asserting that her pages have been run by "teams" of people over the years, some promoting views with which she does not agree. Many of the posts in question have since been scrubbed.

Greene's behavior since her election has been troubling as well. She has peddled false claims that the presidential election was stolen and rife with fraud. She was among the 139 House Republicans who voted to overturn the results of the Electoral College on Jan. 6, even after a pro-Trump mob sacked the Capitol. On Jan. 17, Twitter briefly suspended her account for repeatedly violating its "civic integrity policy."

The silence from Republican leaders has been deafening. That can't continue if the party has any hope of reclaiming conservatism from nihilistic rot — something every American should be rooting for to maintain a healthy two-party system. Greene is now a member of the U.S. House, with a prominent platform and real power to have an effect on people's lives. She has a responsibility to act — and speak — in the best interests of the American public and of the Constitution she has sworn to serve and defend. Peddling grotesque lies, cheering talk of political violence (which she claims to oppose) and fomenting sedition run counter to her oath of office.

With each new revelation, the calls to discipline Greene grow louder. Rep. Jimmy Gomez, D-Calif., plans to introduce a resolution calling for her expulsion from Congress, which had at least 50 members signed on as of Friday. This approach is unlikely to succeed. While the Constitution gives both chambers of Congress wide latitude to punish members, expulsion, which requires a two-thirds majority to pass, has been used rarely over the centuries. Lawmakers prefer to leave it to voters to hand down such a sentence.

Reps. Nikema Williams of Georgia and Sara Jacobs of California plan to introduce a resolution to censure Greene. This penalty is imposed more frequently and requires only a simple majority to pass. It is meant to serve as a badge of shame. Of course, Greene, who revels in shamelessness, might well wear it as a badge of honor — evidence that a corrupt, elitist political establishment was out to get her.

Rep. Debbie Wasserman Schultz of Florida is among those calling for a more appropriate punishment: stripping Greene of her committee assignments. Critics are particularly incensed by Greene's being placed on the Education Committee, in light of her deranged theories on school shootings.

Republicans have recent experience in this area. In 2019, the House minority leader, Kevin McCarthy, stripped Steve King of his committee posts for defending white nationalism in an interview with the New York Times. The Iowa lawmaker had a long history of racist remarks, for which voters had largely given him a pass. But losing his committee assignments did not simply mark King, it drained his influence and his ability to serve constituents. King lost his primary race last year, ending his nine terms in office.

McCarthy needs to take substantive action of this kind with Greene. Voters may have just chosen Greene to represent them, but her Republican colleagues have the leeway to declare that she does not represent them. When Greene's statements about assassinating Pelosi surfaced, McCarthy's office called them "deeply disturbing" and said he would have a talk with her about them this week. McCarthy has an opportunity to make clear that there are standards of decency and duty that transcend partisanship. Others are watching, within his conference and beyond.

Greene has thus far met criticism with defiance. "I will never back down. I will never give up," she said in a statement Friday, which included an ominous warning to her party. "If Republicans cower to the mob, and let the Democrats and the Fake News media take me out, they're opening the door to come after every single Republican until there's none left."

Greene is correct that the Republican Party is facing a serious threat from an unhinged mob. She should know, she's one of its leaders.