The images rippling through Frontline are familiar enough: a mob storming the Capitol.

But beyond that, this edition, Trump's American Carnage (10 p.m. ET, Tuesday, on PBS, check local listings), asks a broader question: How did these people entwine with the stately restraint of the Republican Party?

"We're the party of Lincoln," Bob Corker, the former Republican senator from Tennessee, says in the film. So "demonizing people because of their color or background (is) not the party I grew up in."

It's convenient to point to Donald Trump, but Charles Sykes, a conservative author and former radio host, takes a broader view: "The Republican Party completely capitulated to him."

Certainly, Republicans were wary of Trump. Senators made that clear during the 2016 primaries.

He is "a con artist," said Marco Rubio (Florida).

He's a "race-baiting, xenophobic, religious bigot," said Lindsey Graham (South Carolina).

"The man is a pathological liar," said Ted Cruz (Texas). "He lies with practically every word that comes out of his mouth."

When Trump won, those senators and others fell in line, possibly reflecting a common fact: Often, people rise to the office, becoming better than their campaign postures.

Then came the early signs that this wasn't the case.

Trump didn't have the "beautiful" alternative to Obamacare that he claimed was ready.

Instead, Members of the House, as well as Senators had to piece together their own; when it failed, he blasted them.

Unlike previous presidents, Darlene Superville of the Associated Press says in the film, he would rarely offer specifics. "He was very happy to let others take the lead, and he would just sign the legislation."

Then came the Charlottesville protests. "This was easy," says Jeff Flake, a former Republican senator from Arizona. "If there's white supremacy, you condemn it."

Trump didn't. "He's unwilling to denounce them," says Sykes, the conservative who later wrote the book How the Right Lost Its Mind.

Republicans accepted a trade-off, the film says. With Trump as president, they got things they wanted – the appointment of conservative judges in federal courts and the Supreme Court, plus a massive tax cut that primarily boosted the wealthy. They accepted the rest; from early moments (families separated at the border) to a late one (peaceful protesters gassed and pushed, so Trump could pose at a church holding a Bible), they didn't react.

The public did. Republicans lost the House in 2018, the Senate, and the presidency in 2020.

"They were warned over and over again about who Donald Trump was and what he was capable of doing," Sykes says. "And they looked the other way."

The extreme came when Trump simply claimed he had won.

"The president perpetuated this total untruth about the election," Corker says. "And intelligent, hard-working Americans followed him."

That peaked as he spoke to them on Jan. 6. "He may not have said 'storm the Capitol,'" says Frank Luntz, a conservative pollster. "But that's what they heard."

He did say, "I'll be there with you." Then he returned to the White House and watched on TV as his supporters searched for his vice-president while chanting, "Hang Mike Pence."