(CNN) On Sunday morning, President Donald Trump decided to go after Bob Corker.
"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.' He is also largely responsible for the horrendous Iran Deal!"
Trump didn't leave it there. "Hence, I would fully expect Corker to be a negative voice and stand in the way of our great agenda," he added. "Didn't have the guts to run!"
Trump's comments come days after Corker cast him as an agent of chaos and suggested that Secretary of State Rex Tillerson wasn't receiving enough support from Trump. And they illuminate two fundamental principles about Trump.
The first, which anyone paying attention already knows, is that Trump bends truth -- and often breaks it -- to fit his purposes.
It turns out that Corker didn't beg for Trump's endorsement or make his re-election bid contingent on being endorsed by the president. Quite the opposite, according to two sources who spoke with CNN's Manu Raju Sunday.
"The President called the senator early last week and asked him to reconsider his decision not to seek re-election and reaffirmed that he would have endorsed him, as he has said many times," one source told Raju.
The second thing this Corker episode makes clear is that, strategically speaking, Trump is playing zero-dimensional chess. As in, the only strategy is that there is no strategy.
In the wake of Trump's absolutely stunning 2016 victory, the conventional wisdom -- in political circles -- was that Trump was a strategic genius, always seeing five moves ahead. He was playing three-dimensional chess while the media was still trying to figure out which way pawns could move. The reason no one thought Trump could win was because "we" didn't see the whole board the way he did. No one else saw it that way. Trump was a genius. An unconventional genius but a genius nonetheless.
Every after-action report of the 2016 campaign has put the lie to that idea. Trump and his team didn't think they were going to win. Many of them thought they were going to be blown out. The idea that Trump was executing some sort of master plan and always knew he was going to shock the world just isn't borne out.
Still, when Trump took over the White House the prevailing wisdom was that he had outwitted and outsmarted Democrats. (Lots of Democrats believed that -- as much as they hated to admit it.) But, with each passing day, week and month, it becomes more and more undeniable that Trump has no master plan and is no master strategist. His only guiding principle is his own personal vendettas.
Take the Corker attack as yet another example of Trump's lack of strategic vision.
Yes, Corker is retiring in 2018. But, that means the Tennessee Republican will still be in the Senate for another year. Which means that Corker's vote -- on, say, tax reform -- is something Trump is going to need. (When you only have 52 Republican senators, you have very little margin for error and you need to do everything you can to keep those members happy.)
Why attack Corker then -- and risk making him mad? (And, Corker was mad; "It's a shame the White House has become an adult day care center. Someone obviously missed their shift this morning," he tweeted in response to Trump's tweets Sunday morning.)
Aside from Corker's one vote on tax reform -- or anything else Trump wants to get done in his first two years in office -- Corker is widely regarded in Washington as a serious person, well respected by his colleagues. Corker is also a conservative; this is no John McCain (Ariz.) or Susan Collins (Maine) that Trump is swatting at.
Corker's colleagues -- most notably Senate Majority Leader Mitch McConnell and Senate Majority Whip John Cornyn -- will watch what Trump has done this morning and wonder whether there's any point at all in trusting the President or trying to find common ground. Never forget that the Senate is an extremely clubby institution; they do not look kindly on attacks on their own.
So, why, given all of the downsides, did Trump spend his morning savaging Corker? Simple. Because Corker said something he didn't like, something that called into question the idea of Trump as the all-knowing, always-right figure that he sees in his mind's eye.
Hitting everyone who hits you, of course, isn't a strategy. It's a tactic. And, not a very good one at that.
Based on all of the evidence of Trump's first nine months in office, it's impossible to conclude that he has any sort of comprehensive strategy or theory of the case. He acts (or reacts) and sees what happens. There's no bigger plan that we're not privy to. There's really no plan at all.