WASHINGTON — After President Donald Trump ranted on Twitter against Sen. Bob Corker, R-Tenn., on Sunday morning, Corker shot back: “It’s a shame the White House has become an adult day care center. Someone obviously missed their shift this morning.”

MY TAKE 1: Will more Republicans openly question Trump’s mental state? Is Corker an outlier or a new leader of GOP opposition?

MY TAKE 2: Senate math rules. There are 52 Senate Republicans. Senate Democrats will stick together and deny Trump on measures needing 60 votes. On legislation requiring 51 votes, consider this: Three or four Senate Republicans are already not reliable GOP votes for Trump.

Trump can’t afford to lose Corker, even with Vice President Mike Pence’s tie-breaking power.

OPINION

With all the massive issues Trump has on his plate — Hurricanes Nate, Maria, Irma and Harvey, income tax reform, immigration, Obamacare repeal and replacement, North Korea and Iran — Trump decided on Sunday to use his vast power to influence the conversation in the country to attack Corker.

A few hours later, Trump injected the NFL player protest back in the news. Trump wrote on Twitter he instructed Pence to leave the Colts game if any players kneeled.

Which some did.

So Pence left.

Let’s break this down . . .

WHY BOB CORKER?

Corker, a former Chattanooga mayor first elected to the Senate in 2006, is the chairman of the Foreign Relations Committee. He is a power in the Senate.

Until this summer, Corker has been an ally of Trump. He was a long-shot Secretary of State contender.
Significant fault lines started developing between Trump and Corker in August, as Corker raised questions about Trump’s capacity to govern.

In mid-August, in the wake of Trump’s response to the violence in Charlottesville, Virginia, giving white nationalists parity with the people protesting them, Corker told reporters in Tennessee, “The president has not yet been able to demonstrate the stability nor some of the competence that he needs to demonstrate in order to be successful. . . . And we need for him to be successful. Our nation needs for him to be successful.”

Last week, talking to reporters after the NBC report that Secretary of State Rex Tillerson called Trump a “moron,” Corker said, “I think Secretary Tillerson, Secretary Mattis, and Chief of Staff Kelly are those people that help separate our country from chaos, and I support them very much.”

Also last week, Corker announced he would not run for another term in 2018. Still, Corker will be around until early January 2019.

TRUMP SUNDAY TWITTER ATTACK

Trump got this ball rolling on Twitter Sunday morning when he wrote “Senator Bob Corker “begged” me to endorse him for re-election in Tennessee. 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.” He is also largely responsible for the horrendous Iran Deal!”

“Hence, I would fully expect Corker to be a negative voice and stand in the way of our great agenda. Didn’t have the guts to run!”

FACT CHECK 1: Corker joined other Republicans in strongly opposing the deal to curb the ability of Iran to develop a nuclear weapon. Perhaps Trump is referring to Corker’s role in getting a Senate floor vote on the Iran deal even as he opposed agreement.

FACT CHECK 2: Did Corker “beg” for a Trump endorsement? Here’s what Corker’s Chief of Staff Todd Womack told NBC News Sunday, “Last week President Trump called Senator Corker and asked him to reconsider his decision not to seek reelection and said I would have endorsed you.”

MY TAKE 3: Even if Trump is angry at Corker — for the adult day care center jab — or for the other cracks, Trump may have alienated an ally whom he needs.