For six months, Mr. Trump has had unfettered access to intelligence on the hacking. He has had six months to authorize covert action, propose tougher economic sanctions, order a more muscular diplomatic response and protect election systems. He has done nothing that meets the eye. Instead, the White House is lobbying against legislation passed by the Senate this month imposing stricter sanctions on Moscow, in part because the bill contains a provision making it harder for Mr. Trump to lift them. And the White House is considering returning to Moscow two compounds in the United States used by Russian spies that were seized by the Obama administration in late December.

In a Jan. 6 report, the intelligence community called Russian efforts to influence the election “the most recent expression of Moscow’s longstanding desire to undermine the U.S.-led liberal democratic order, but these activities demonstrated a significant escalation in directness, level of activity, and scope of effort compared to previous operations.” In a warning that action needs to be taken now, intelligence officials say Russia will redouble its efforts in the United States and elsewhere after its success in 2016 and that electoral mechanisms need to be shored up before the congressional election of 2018, and in European nations, which are even more vulnerable.

Over the weekend, Mr. Trump, who has downplayed reports of Russian electoral interference and possible collusion with his campaign, was acting as if The Post’s report was the first he’d heard of the Russian threat. Seizing the opportunity to change the subject from the F.B.I.’s investigation into his team and whether he obstructed that inquiry, he criticized Mr. Obama.

“The reason that President Obama did NOTHING about Russia after being notified by the CIA of meddling is that he expected Clinton would win...and did not want to ‘rock the boat,’ ” he tweeted on Monday. “He didn’t ‘choke,’ he colluded or obstructed, and it did the Dems and Crooked Hillary no good.”

With those tweets was Mr. Trump acknowledging what he hasn’t before, that Russia intended to help him? As late as last week, he tried to discredit his intelligence agencies’ findings to that effect as a Democratic “HOAX” and “excuse for losing the election.” But on Monday he seemed to be saying that Mr. Obama didn’t address Russia’s meddling only because he thought Mrs. Clinton would win anyway. Either way, the intelligence community has established that Moscow aimed to help Mr. Trump win, and that should color perceptions of every move he makes.