On Sunday morning, President Trump awoke and decided to pursue a favorite weekend pastime—not golf, but starting a Twitter fight. This time, he attacked Tennessee Senator Bob Corker, the respected two-term Republican who chairs the Senate Foreign Relations Committee and once was in the running to become Trump’s Secretary of State.
“Senator Bob Corker ‘begged’ me to endorse him for re-election in Tennessee,” Trump tweeted. “I said ‘NO’ and he dropped out (said he could not win without…my endorsement). He also wanted to be Secretary of State, I said ‘NO THANKS.’”
Trump’s claim is almost certainly untrue. Corker, who announced his retirement on Sept. 26, denied asking for an endorsement and, furthermore, told The New York Times that Trump had recently asked him to reconsider his decision not to run again. Having already committed to bowing out when his current term ends, Corker was free to hit back and did so with gusto. “It’s a shame the White House has become an adult day care center,” he replied on Twitter. “Someone obviously missed their shift this morning.”
Like many of the president’s tweets, the attack on Corker seemed designed to compensate for a private anxiety—in this case, that Trump’s endorsement may not be all that valuable. That would be a serious blow to Trump’s ego. But it could be a bigger blow to Republicans’ electoral fortunes.
Here’s why: GOP lawmakers have stood by Trump through countless embarrassments and indignities because they believed that his support—which remains strong among his voters—would transfer to those upon whom he bestows his endorsement. This is crucial because midterm elections are always difficult for the party in power. If voters are unhappy, they know whom to blame. And Republicans’ failure to move their legislative agenda means that many incumbents up for reelection are desperate to give them a reason why they…