It’s reminiscent of the old parody motivational poster that reads, “The beatings will continue until morale improves.” Or, in Trump’s case: “The tweeting will continue until the chyrons improve.” In the past, this has worked well for Trump. His ability to change the subject has managed to prevent sustained attention on some of the biggest scandals of his political career. But there are limitations to this tactic, as the oxymoronic poster suggests, and they may be emerging right now.

You don’t have to look hard to see what Trump was upset about. Even though Mueller’s testimony to the House Judiciary and Intelligence Committees was short on dramatic sound bites, and the infernal “optics” debate seemed to favor Republicans in the first day or so, it became clear by week’s end that this wasn’t the death knell for investigations that the GOP had hoped it would be. House Speaker Nancy Pelosi didn’t come around on impeachment, but Democrats also showed they were not going to drop the matter and move on. The chairs of the two committees, Jerry Nadler and Adam Schiff, seemed perhaps more resolved to move forward after the hearings.

On Friday, some Democrats said they were conducting an impeachment investigation—while hastening to add that didn’t mean that actually impeaching Trump was a foregone conclusion. And on Thursday, in the move that drew the president’s fury, Cummings’s Oversight Committee approved subpoenas for White House communications from the senior advisers Ivanka Trump and Jared Kushner, as well as the former strategist Steve Bannon.

House Democrats: Why we’re moving forward with impeachment

There are several reasons to question the efficacy of Trump’s distraction here. The first is that it means that a piece of good news for the president Friday afternoon, a Supreme Court decision that allows the Trump administration to begin work on a wall on the southern border while litigation continues, has been largely overlooked.

A second is the same as the point that I and many others made after Trump’s attack on the squad: Exploiting racial tension has been a successful strategy for Trump and many other politicians, but open racism is, in addition to its moral repugnance, a risky electoral ploy.

Third, and perhaps most important, a distraction works only if it distracts. Trump has successfully turned the conversation to his tweets about Cummings, but he has not turned it away from impeachment. In fact, he’s deepened his problems: As of yesterday, 107 House Democrats back an impeachment inquiry, up from the mid-90s last week. That’s almost half the caucus. Non–House members, including Patty Murray, a top Senate Democrat, have also voiced support.

David A. Graham: Trump’s impeachment finger trap

This is in part a testament to Cummings’s standing inside the caucus. There have been tensions between more establishment Democrats and the squad since the start of the Congress—notably between Pelosi and the foursome. When Trump attacked them, Democrats rallied against him, but they may have hesitated to line up too loudly behind the rabble-rousers. Cummings, however, is a 23-year House veteran, a committee chair, and former chair of the Congressional Black Caucus. As my colleague Peter Nicholas notes, he was also a Democrat who was willing to work with the White House, so Trump’s attack shows that he’s willing to go scorched-earth even on members who are far more restrained than Ilhan Omar. The president may have underestimated the extent to which Democrats would rally around Cummings.