For some critics, it seemed to be a cynical way of distracting attention from the multiple investigations into possible contacts between associates of Mr. Trump and Russia even as Moscow was trying to help Mr. Trump win the presidency.
Either way, it suggested that the relationship between the two powers could be volatile in the months to come, subject to the impulsive reactions of a president with no prior experience in foreign policy, the often strident responses of a Russian leader given to his own moments of pique and the clashing national interests of both countries in key areas around the world.
“I was skeptical from the beginning that it would be possible for the United States and Russia, after all that happened in the last few years, to engage in a successful reset,” said Angela Stent, a former national intelligence officer on Russia now at Georgetown University. “What’s surprising is how quickly we returned to the status quo ante we had at the end of the Obama administration.”
John R. Beyrle, a former ambassador to Moscow, said the extremes of the relationship were being exaggerated and it would probably settle back into the middle. “Levels of trust have deteriorated so much that these initial meetings will produce little in the way of agreements and the investigations into likely Russian interference in the election cast a huge shadow that both sides need to acknowledge,” he said.
Mr. Trump is the fourth president in a row who came into office determined to reboot the relationship with Moscow, an ambition that often eluded the other three. The difference is that the hacking of Democratic email during last year’s election, for which intelligence agencies blamed Russia, made Mr. Trump’s embrace of Mr. Putin politically problematic.
His willingness to overlook Russia’s annexation of Crimea, its armed intervention in eastern Ukraine and, until now, its support for President Bashar al-Assad’s government in Syriamystified many experts. He called Mr. Putin “a stronger leader” than President Barack Obama, praised him for “doing a great job” and expressed hope that he would be “my new best friend.” Michael Morell, a former acting C.I.A. director, wrote last fall that Mr. Trump seemed to be an “unwitting agent of influence” for Moscow.
By Tuesday, after Mr. Trump ordered a missile strike against Syria in retaliation for using chemical weapons on its own people, Secretary of State Rex W. Tillerson arrived in Moscow with a harsh warning that Russia had better give up its support of Mr. Assad. He was greeted with a cold shoulder, denied a meeting with Mr. Putin as no secretary of state has been on a first visit to Moscow going back to the days of Cordell Hull in World War II. Back in Washington, the White House held a briefing accusing Russia of shielding Syria’s chemical weapons attack on civilians.
The Russians have responded with harsh language of their own. On Tuesday, Mr. Putin compared Mr. Trump’s action in Syria to President George W. Bush’s invasion of Iraq in 2003. And Prime Minister Dmitri A. Medvedev suggested that Mr. Trump has turned out not to be what he presented himself to be during last year’s campaign.
“That’s it,” he wrote on Facebook last week. “The last remaining election fog has lifted.” In the end, he said, Mr. Trump was “broken by the existing power machine” in Washington.
Mr. Morell said on Tuesday that despite calling Mr. Trump a virtual Russian agent, he always believed Russian behavior would lead to a parting of the ways. “This seems to be happening now,” he said. But he noted that Mr. Trump has left it to Mr. Tillerson and others rather than speaking out himself.
“He needs to do that, and he needs to be critical of the large number of other aggressive actions that Putin has undertaken over the past two years,” Mr. Morell said.
Jennifer Palmieri, the communications director for Hillary Clinton’s campaign last year, said the shift in tone in recent days did not mean there was not collusion during the election. “Everything we believed happened in the election could be true — Putin wanted him to be president and the administration took the action it took last week,” she said. “It could all be part of the master ruse — or Putin could be upset about it.”
Either way, she said, “There’s no evidence that it changes anything I think happened in the election or that Democrats should back off investigations. And moreover, it’s really weird that he himself hasn’t said anything.”
Mr. Trump will have the opportunity on Wednesday when he hosts NATO’s secretary general, Jens Stoltenberg. European leaders will be listening to what Mr. Trump has to say, given that during the campaign he criticized NATO even as he praised Mr. Putin.
Aides to Mr. Trump have been frustrated at the focus on the Russia investigations and the assumptions that the president’s associates did something wrong even though several officials have said no evidence has emerged that proves collusion with Russia. They blame the media for creating a false narrative that they see as now disproved. How, they ask, could Mr. Trump’s team have made secret deals with Russia if his own secretary of state cannot even get a meeting?
“It’s interesting that we went from all of these direct links to Russia to now are we disappointed that we can’t even get a meeting with him,” Sean Spicer, the White House press secretary. “There is a bit of irony in the question.”
Eric Trump voiced that sentiment in an interview with London’s Daily Telegraph published on Tuesday. The younger Mr. Trump said his father was influenced to retaliate against Syria for using chemical weapons on civilians in part by his sister Ivanka, who was “heartbroken and outraged” by the atrocity.
Even though some question the president’s approach to Russia, Eric Trump said his father would not be “pushed around” by Mr. Putin. “He is not a guy who gets intimidated,” he said.
The back-and-forth over Russia left lawmakers trying to make sense of it.
“It speaks to the broader incoherence of this administration’s foreign policy,” said Senator Chris Murphy, Democrat of Connecticut. “The change in rhetoric on Russia is head-spinning. I’m glad to see it and I hope it continues, but so far the only thing we know about this administration’s foreign policy is that it will probably change in a week or two.”
But Mr. Murphy said the congressional intelligence committees still need to investigate what happened in last year’s election. If the shift in tone from the administration happened two months ago, he said, it might have undercut that determination. But since then, he said, more evidence has emerged.
“There’s now some pretty important meat on the bones of this story,” he said. “The imperative remains to get to the bottom of it.”
Correction: April 12, 2017
Earlier versions of this article misspelled the last name of a former acting director of the C.I.A. He is Michael Morell, not Morrell.