Donald Trump tends to operate by predictable rules: if he hears about someone of note criticizing him, the president returns fire, aggressively, wildly, and frequently to his own detriment. He can’t seem to help himself.

Over the last week or so, however, we’ve seen some extraordinary and uncharacteristic restraint from the Oval Office. Cliff Sims, who worked with Trump during the campaign, and ultimately became the White House’s director of message strategy, wrote a book called Team of Vipers, which includes some unflattering portraits of the president and his team.

As excerpts and anecdotes from Sims’ book started to generate attention, I more or less assumed Trump would lash out, but we were instead confronted with … silence.

Last night, The Daily Beast marveled at the White House’s self-control.

Trump, the sources added, expressed multiple times last week a strong desire to rage-tweet against Sims, even soliciting advice on what language and put-downs he should use. Those sources said that senior Trump aides including Jared Kushner (portrayed as a key villain in Christie’s Let Me Finish: Trump, the Kushners, Bannon, New Jersey, and the Power of In-Your-Face Politics) and Kellyanne Conway (portrayed as a key villain in Team of Vipers) successfully counseled the president not to do so, arguing that it would give the situation more attention. As of Monday evening, the rage has been largely bottled, much to the surprise of those who’ve worked with Trump.

A former White House official, expressing some optimism about the competence from the president’s new communications department, added, “If Trump can go the next 24 hours without tweeting about it, the book will be out of the news cycle by this Wednesday.”

He didn’t quite make it 12 hours.

“A low level staffer that I hardly knew named Cliff Sims wrote yet another boring book based on made up stories and fiction,” Trump wrote on Twitter this morning. “He pretended to be an insider when in fact he was nothing more than a gofer. He signed a non-disclosure agreement. He is a mess!”

All the president had to say was nothing. It looked like he’d succeed, to the delight of those around him.

But then he apparently saw Sims on his television screen, at which point Trump’s lack of impulse control quickly overrode the advice of his own team.

Time will tell whether this backfires – I imagine Sims will be delighted by the inadvertent public-relations assistance from his former boss – but either way, the president’s complete absence of discipline is a poor trait in a leader with so much power.