GOP dam breaks as impeachment vote takes on greater meanings: The Note

The TAKE with Rick Klein

President Donald Trump is about to become the first president to be impeached twice. The second one, while unlikely to drive him from office early, will almost certainly be the one that matters the most.

The House vote Wednesday will be bipartisan and resounding. It will include at least one member of Republican leadership and the math may be even worse for the president in the Senate.

It will constitute a stinging judgment on Trump and his political movement. But it is unlikely to constitute the final words on either topic -- and the power of words mark one reason that the impeachment vote has grown in importance as it has approached.

Members of Congress will be voting in the same chambers that were attacked by a violent mob just a week ago. Many of them were almost harmed, and threats to their safety over the next week are growing even while Trump has deflected from taking responsibility.

There will be no witnesses in this trial, in part because those voting on it are themselves all witnesses. They saw what happened last week -- and see what could still happen over the next week and well beyond, whether or not they act to rebuke the president.

"The president of the United States summoned this mob, assembled the mob, and lit the flame of this attack," Rep. Liz Cheney, the third-ranking House Republican, said in announcing she would vote to impeach.

Members of both parties have watched Trump and his remaining defenders seek to redefine realities while they explain away and minimize Wednesday's atrocities.

Those attacks -- attacks on facts -- are part of what's on trial in Congress now. Self-interest is in no doubt in play in Republicans for ditching Trump now -- but judgments on the importance of facts and truth matter along with judgments on the president himself.

The RUNDOWN with MaryAlice Parks

Two headlines Tuesday illustrate the anxiety, distrust and security concerns overwhelming Washington this week.

First, Republican House members expressed anger and frustration after being asked by leadership to go through a new metal detector before entering the House chamber.

At least one member has been adamant about carrying a weapon on the Hill as of late, and it has worried colleagues.

The same day too, all of the Joint Chiefs of Staff signed onto a stunning internal memo to members of the military reminding them that their mission is to defend the Constitution and any act to disrupt the Constitutional process, including the inauguration of President-elect Joe Biden next week, would be "against the law."

"As Service Members, we must embody the values and ideas of the Nation. We support and defend the Constitution," they wrote.

The very fact that they felt compelled to draft such a notice suggested nervousness about loyalties in their own ranks -- a chilling possibility for a nation already on edge.

The TIP with Meg Cunningham

As Republicans in Congress turn their backs on Trump, party officials in Arizona are holding onto him for dear life by reportedly introducing new text to censure some party members who have at times opposed the president. Reports from local news stations reveal that the party plans to vote on censures for Cindy McCain, Gov. Doug Ducey and former Sen. Jeff Flake, who have all had moments of breaking with the GOP since Trump took office.

The party is set to meet on Jan. 23 to take up a new platform, which, according to an NBC affiliate in Phoenix, will censure the three Republicans. The Arizona GOP did not return ABC News' request for the proposed censure documents. Cindy McCain and her daughter, Meghan McCain, responded to the reported plans by pointing to Chairwoman Kelli Ward's lack of statewide wins in her time as a public servant in Arizona. The party censured the late-Sen. John McCain in 2014, although he went on to beat Ward in a 2016 primary for another term.

Ducey came under attack from the party after his refusal to overturn election results in favor of Trump and Flake will reportedly be censured for his support of "progressive" and "leftist" politicians. The votes to censure are yet another sign of how a lack of GOP leadership and message have left many state parties without a clear agenda aside from unwavering support for Trump.

The PLAYLIST

ABC News' "Start Here" podcast. Wednesday morning's episode features ABC News Senior Congressional correspondent Mary Bruce, who previews Wednesday's impeachment vote against President Donald Trump for his role in the Capitol riot. ABC News Chief Justice correspondent Pierre Thomas tells us what the FBI knew before the attack was carried out. And ABC News contributor, retired Col. Stephen Ganyard, examines how foreign adversaries may be taking advantage of the unrest in the U.S. as Joe Biden prepares to take office. http://apple.co/2HPocUL

ABC News' "Powerhouse Politics" Podcast. Political consultant and pollster Frank Luntz joins ABC News' Chief White House correspondent Jonathan Karl and Political Director Rick Klein. https://bit.ly/2w091jE

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