President Trump is increasingly directing his frustrations at specific Senate Republicans, and turning his fire in recent days on key allies.

The president this week publicly excoriated Sens. Chuck Grassley (R-Iowa) and Josh Hawley (R-Mo.) over upholding the “blue slip” tradition and pushing a congressional stock trading ban, respectively.

While Trump has long had a tendency of airing his grievances out in public especially toward those he views as disloyal the latest barbs about staunch backers are raising eyebrows and drawing questions about whether the strategy will continue to be effective in advancing his agenda.

“I don’t think it’s helpful for the president … to get in a tit for tat with other Republican members,” said Sen. Shelley Moore Capito (R-W.Va.), a member of GOP leadership. “He needs every single one of us, and we need him.” 

Trump has repeatedly tangled with Sen. Rand Paul (Ky.), a libertarian-minded Republican who is not shy about voting against the president’s priorities, as well as Sen. Mitch McConnell (R-Ky.), the former Senate GOP leader who once spoke out against Trump, has voted against several of his nominees and has become a leading voice in favor of the Ukraine aid Trump often rails against.

Earlier this summer, he put off some Senate Republicans by attacking Sen. Thom Tillis (R-N.C.) over his opposition to Trump’s “big, beautiful bill.” A number of Republicans indicated they were not big fans of the way the president went after a vulnerable incumbent seen as a team player, and one who had helped advance key Trump nominees. Tillis announced his retirement shortly after.

But Trump seemingly crossed another line with Republican lawmakers this week by not only calling to eliminate the “blue slip” process which gives veto power to senators for district judge and U.S. attorney picks for their individual state but by going after Grassley personally. The 91-year-old Iowa Republican is the most senior member of the Senate GOP conference and is both well-liked and respected in the Capitol.

Trump posted on Truth Social that he got Grassley reelected to the Senate “when he was down by a lot,” then reposted other commenters who urged followers to “light up Grassley’s office” and called Grassley a “RINO,” the acronym for Republican in name only, “sneaky” and “good at playing the good guy instead of being the good guy.”

“They’re very angry about how Grassley was treated, because he’s one of the fairest people that’s walked these halls,” one Senate GOP member told The Hill. “It was the wrong fight to pick.”

Sen. Mike Rounds (R-S.D.) said the attack on Grassley surprised him.

“I think the president may have gotten some bad information from somebody,” he said. 

Trump also found a dearth of support in the Senate GOP conference for ending the “blue slip” tradition, which hands the minority party some control over the process. 

Sen. Tommy Tuberville (R-Ala.), an ardent Trump backer, noted he used them to block judges in his home state during former President Biden’s White House tenure.

“I know that Sen. Grassley has worked really hard to defend the president’s nomination, and we all support the blue slip process,” Rounds said. “That is one power and one authority that the Senate will give up. We are not going to turn that over to the executive branch alone.” 

Two days later, Trump went after Hawley personally on Truth Social over him siding with Democrats to back a congressional stock trading ban that also extends to presidents and vice presidents. 

“Why would one ‘Republican,’ Senator Josh Hawley from the Great State of Missouri, join with all of the Democrats to block a Review, sponsored by Senator Rick Scott, and with the support of almost all other Republicans, of Nancy Pelosi’s Stock Trading over the last 25 years. The information was inappropriately released just minutes before the Vote Very much like SABOTAGE!” Trump wrote on Truth Social.

Although Hawley’s level of support in the conference isn’t near Grassley’s, he is still a fan favorite of the MAGA base. 

The Missouri Republican said Thursday he spoke with Trump on Wednesday night after the social media broadside and made clear to him that he wasn’t targeting him by siding with Democrats. While the stock ban he proposed would affect presidents, it wouldn’t go into effect until 2029, meaning it wouldn’t be imposed against Trump himself.

Hawley said Trump was under the impression from other Senate Republicans that he would be affected. 

In total, Senate GOP sources believe the more Trump goes after people who are largely supportive of his legislative and nomination efforts, the less effective they get over time. 

“It dilutes the threat of him criticizing people for actually opposing his agenda if he’s criticizing people for Republican mainstream positions,” one Senate GOP aide said, specifically pointing to the Iowa Republican. 

Another Senate Republican agreed. 

“I think that he’s dropping a couple of more proverbial straws and he probably needs to proceed with caution,” the Senate GOP member said. “You reach a point where if you go after so many people, the people you haven’t gone after start wondering if they’re next and that’s when maybe institutional protection becomes a priority here.” 

Trump, however, has also shown restraint at times. He has notably not publicly attacked Sen. Susan Collins (R-Maine) despite her vote against the “big, beautiful bill” and the bill clawing back public media and foreign aid funding, along with a couple of his high-priority nominees. 

And some top allies believe Trump’s barbs are effective.

“That’s his forte. … He is spreading the wealth,” Tuberville said with a laugh. “He is holding back on nobody. He knows his game plan and he’s going to implement it and he thinks he needs more help.” 

Others believe it’s yet another sign that it’s time for the chamber to recess for the August break as members become increasingly cranky. Capito specifically pointed to the war of words between Hawley and Sen. Rick Scott (R-Fla.) over the stock trading ban at the Senate Homeland Security and Governmental Affairs Committee on Wednesday, and Sen. Cory Booker’s (D-N.J.) diatribe against his Democratic colleagues on top of Trump’s attack on Grassley.

“Everybody’s going after everybody,” Capito said. “It’s the hot summer. I think it’s just indicative that it’s time to take a breath.” 

“It’s the reason why August is a miserable time here in D.C.,” she added. “We’re exemplifying it.”