Thornberry and Graham are both grappling in their own ways with a conundrum facing Republicans, in both the House and the Senate. Most of them know what their conclusion is—Trump is innocent and should not be impeached or removed—but they haven’t figured out why, and no one is helping them out.

Typically, this is the sort of role that the White House would play, with a war room designing and pushing out a message. But Trump has declined to set up such an operation, relying on his Twitter account to push his message. “He is the war room,” Press Secretary Stephanie Grisham told Fox News earlier this month. If Twitter is the president’s army, it’s a fighting force that’s ready and willing to go over the top at a moment’s notice, but one that eschews any kind of long-term strategic planning.

David A. Graham: Republicans have only three choices

The White House has made clear that it will launch an all-out offensive against any Republican who dares to criticize the president at all. As for affirmative defenses, the White House’s line—which is to say the president’s—is that Trump did absolutely nothing wrong or inappropriate, as he reiterated Sunday:

The call to the Ukrainian President was PERFECT. Read the Transcript! There was NOTHING said that was in any way wrong. Republicans, don’t be led into the fools trap of saying it was not perfect, but is not impeachable. No, it is much stronger than that. NOTHING WAS DONE WRONG! — Donald J. Trump (@realDonaldTrump) November 10, 2019

While a few Republicans are willing to adopt this line of argument, most are not. It’s simply a very hard claim to make based on the factual evidence, and consistently about two-thirds of Americans tell pollsters they believe that what Trump did was inappropriate.

Republicans aren’t getting much messaging help from the second-most powerful official in the party either. Senate Majority Leader Mitch McConnell told caucus members at a meeting in October that “their best bet was to calibrate their own message about the impeachment inquiry to fit their political situation,” according to the Associated Press. McConnell himself has studiously avoided taking a stance. In October, he pointedly denied telling Trump his July 25 conversation with Ukrainian President Volodymyr Zelensky was “the most innocent phone call that I’ve read,” but did not offer an alternative assessment.

A few Republicans have either labeled Trump’s call wrong or managed to avoid commenting. (Igor Bobic has a useful list on Senate Republican views.) But in the absence of guidance, the majority of Republican members who are trying to stick with Trump have been left to fend for themselves and come up with defenses. They’ve ended up in three main categories:

The president did nothing wrong. The advantage of this position is that it puts you on the same side as the president, and means he won’t be taking shots at you publicly, the way he has at some other Republicans. The disadvantage is it puts you on the same side as the president—and against the judgment of most Americans. (Some of the people espousing it have constituencies that may be more Trump-friendly than the general populace.)