WASHINGTON — In the ongoing war between President Donald Trump and Sen. Bob Corker, R-Tenn., both sides have been bloodied — and the president's relationship with the establishment GOP has deteriorated further.
There also may be no immediate relief from the political carnage for the many Republicans who are averting their eyes and hoping Trump's attacks don't upend his agenda, or theirs.
That's because neither man has an incentive to back down. Corker is freed from the constraint of needing the president's political support after having announced that he won't seek re-election, and there's a certain logic behind Trump's itchy Twitter finger, which tapped out the mocking sobriquet "Liddle' Bob Corker" Tuesday morning.
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"The president is channeling the views of a lot of conservatives who still feel burned by the Iran nuclear deal and who feel that (Corker) is a bit of a chickenhawk when it comes to conservative issues," said Matt Schlapp, the chairman of the American Conservative Union and a Trump ally.
"He clearly is demonstrating that his party does not dominate his judgment on everything, so he’s OK with going after these Republicans who are unreliable on key issues," Schlapp added. "He tends to pick targets that have been bothering Republicans for a long period of time."
The tiff with Corker is a classic Trump fight — public, brash and with a member of his own party. But it's one that some Republicans see as particularly dangerous, given Corker's centrality to the GOP’s hopes of getting anything big done in Congress by the end of the year and the dwindling patience of Corker's colleagues.
"I don’t think anyone wins," said Christian Ferry, founder of the Trailblazer Group and manager of Sen. Lindsey Graham's 2016 presidential campaign. "It just continues us on the path of complete dysfunction."
Sarah Huckabee Sanders, the White House press secretary, continued the dispute Tuesday afternoon, framing Corker as an architect of the Iran nuclear deal that Trump has trashed and advising the senator to "stop taking vacations." A spokesperson for Corker disputed he was responsible for the Iran deal and the senator’s chief of staff stepped out from behind the scenes to try to set the record straight on Twitter.
Bob Corker led opposition to the #Irandeal in Congress that resulted in a bipartisan vote AGAINST the deal.
Corker was actually one of Trump’s closer allies in the Senate, and reportedly put on short-lists for both the vice presidency and secretary of state. During the campaign, he reliably defended Trump from what he called the "fecklessness and ineptness of the Washington establishment."
Corker, chairman of the Senate Foreign Relations Committee, certainly has more friends in the GOP cloakroom than Trump. And the president's picking yet another fight with yet another GOP senator is unlikely to shore up the party's narrow two-seat majority in the Senate.
So their falling out is another sign of Trump’s isolation from his own party in Washington. That’s lamentable, perhaps, for the GOP policy agenda, but it’s a comfortable political position for an outsider who has to find a way to run against a capital city he and his party now control.
That's the strategy employed by former Trump chief strategist Steve Bannon, who is trying to recruit primary challengers to sitting GOP lawmakers. In an interview with Sean Hannity on Fox News, Bannon said Corker should "resign immediately" and take the rest of the "establishment globalist clique on Capitol Hill" with him.
It's getting crowded in Trump’s Twitter doghouse.
Among Senate Republicans, there’s Majority Leader Mitch McConnell ("he failed!") and Rand Paul ("such a negative force"), both of Kentucky; Jeff Flake ("He's toxic!") and John McCain ("Let Arizona down!"), both of Arizona; and Lisa Murkowski of Alaska ("really let the Republicans, and our country, down").
The president has gone after so many fellow Republicans that he’s started re-using epithets. “Little” was his dig at Sen. Marco Rubio of Florida, but he told The New York Times that the proper spelling was, "L-I-D-D-L-E. Liddle, Liddle, Liddle Marco," which he has now been repurposed for Corker.
But even some Democrats, who often cheer on Republican infighting, are cringing at this latest mess.
"It’s really unfortunate that the president has chosen to blast him in a series of tweets that were both distracting and disrespectful," Sen. Chris Coon of Delaware, a member of the Foreign Relations Committee, said on a conference call Tuesday, referring to Corker.
Tom Griscom, a Chattanooga-based Republican strategist, said Trump's manner of trying to influence lawmakers — often going after them personally, and not sparing those in his own party — comes with risks.
"This is his way of thinking that he can impact policy and move people in a certain direction, and this is his way of doing it," Griscom said. "Does this really help us in formulating public policy and building reassurance for the things that are important for America, not just here but around the world?"
The tensions, lawmakers and outsiders agree, are unlikely to restore any sense of order as Congress prepares to again debate the Iran nuclear agreement and deal with ongoing threats from Iran, Russia and North Korea.
"It doesn't really matter what he says about Corker, and it doesn't really matter what Corker says about him," Graham told MSNBC on Tuesday. "I don’t think it’s good. I don’t think it is healthy."
Alex Seitz-Wald is senior digital politics reporter for NBC News.
Jonathan Allen is a senior political analyst for NBC News, based in Washington.