To measure how far and how fast the Republican Party has been overtaken by its fringe elements, compare the cases of Reps. Marjorie Taylor Greene (R-Ga.) and Steve King (R-Iowa).

Greene arrived in Congress last month, instantly infamous for her embrace of QAnon and other conspiracy theories. So far she has been accommodated — and even encouraged — by party leadership. King, meanwhile, just departed Congress after 18 years, turned out by voters two years after Republicans made him a pariah and stripped him of his committee assignments for defending white nationalism to The New York Times.

Looking at Greene, you have to wonder if King would still be serving if the incident had happened today.

Greene, after all, was already known for promoting QAnon's nutty theories by the time she was elected. New revelations have made the picture look even worse: It appears that in recent years she liked a social media comment calling for the executions of House Speaker Nancy Pelosi (D-Calif.) and FBI agents investigating Donald Trump; speculated that California wildfires were caused by space-based lasers controlled by the Rothschild family, a frequent bogeyman for anti-Semites; and endorsed the false notion that the Sandy Hook and Parkland school massacres were "false flag" operations designed to rob Americans of their gun rights.

Through it all, Greene has expressed an affinity for political violence.

"If this generation doesn't stand up and defend freedom, it's gone," she said in a video made before the election, but which drew public attention last week. "And once it's gone, freedom doesn't come back by itself. The only way you get your freedoms back is it's earned with the price of blood."

Officially, GOP leaders in Congress disapprove of all this, though their objections are tepid.

"These comments are deeply disturbing, and Leader McCarthy plans to have a conversation with the congresswoman about them," a spokesman for House Minority Leader Kevin McCarthy (R-Calif.) said last week.

Whatever happens in that conversation, it is also true that Republicans have already assigned Greene to the House Education Committee. And that she is touting Trump's support after a phone call last week. On Sunday, Arkansas Gov. Asa Hutchinson (R) on Sunday tried to sidestep the question of Greene's fitness for Congress. Hutchinson said he rejected her stances, but: "I'm not gonna answer that question as to whether she's fit to serve, because she believes in something that everybody else does not accept."

One of the functions of a political party, though, is to determine if politicians are fit to serve under its banner. Part of that is deciding what beliefs are — and are not — acceptable.

Certainly, Republicans were able to do that quickly after King's comments to The New York Times in January 2019. "White nationalist, white supremacist, Western civilization — how did that language become offensive?" King mused to the paper. The backlash was quick and severe.

"That is not the America I know, and it is most definitely not the party of Lincoln," McCarthy said at the time. "Action will be taken. I'm having a serious conversation with Congressman Steve King on his future and role in this Republican Party." King was soon after stripped of his committee assignments, left powerless, and rendered vulnerable to voters who wanted more effective representation.

But the GOP that kicked King to the curb just two years ago seems to have shed any last vestiges of responsibility. The Republican Party's pariahs now are people like Reps. Liz Cheney (Wyo.) and Adam Kinzinger (Ill.), who voted to impeach Trump for inciting the Capitol insurrection — and who voted to certify Joe Biden's presidential victory. The Arizona Republican Party has censured its own governor for failing to stand with Trump's false allegations of voter fraud, while the Oregon GOP proclaimed the insurrection a "false flag" operation and condemned the 10 Republicans who voted for impeachment.

The members of the Republican Party, then, are making it absolutely clear who they believe are fit to serve. The answers are dismaying. Steve King said some terrible things — but the experience of Marjorie Taylor Greene suggests that as far as the GOP is concerned, King was simply ahead of his time.