(CNN) President Donald Trump hoped his hotly anticipated summit talks with Russian counterpart Vladimir Putin would amount to a triumphant television event. Instead, he returns to Washington facing sharp rebukes even from allies as his stunned aides wonder what went wrong.

For many of Trump's advisers, Monday's performance amounted to a worst-case ending to a summit few in the administration believed was well-timed. From the moment Trump raised the potential for a meeting during a congratulatory phone call to Putin in March, top national security staff argued there was little evidence a sit-down would prove effective, particularly given Moscow's continued efforts to destabilize Western alliances.

But Trump paid little heed, insisting the meeting was necessary to fulfill his stated goal of improving the relationship between the US and Russia. And so planning began for Monday's event in Helsinki , a site selected by aides for its historic ties to Washington-Moscow diplomacy. In the lead-up, administration officials from Trump on down sought to dampen expectations, even as television cameras began crowding into Senate Square.

Those diminished expectations did little to quiet the collective shudder in Washington.

"This was not the plan," said a US official directly involved with Helsinki summit, summing up the deflated response from an administration already suffering burnout, fatigue and disillusionment.

In the hours after Trump's appearance alongside Putin in the columned-and-chandeliered Hall of State, White House officials openly admitted they don't know how to respond to questions about Trump's striking declaration that Putin was "extremely strong and powerful in his denial" of election interference.

Aides who traveled with the President in Europe boarded Air Force One around 8:30 pm Helsinki time Monday, leaving those back in Washington to field inquiries for the next eight-and-a-half hours. Those who answered their phones didn't have much to say.

"How bad was that?" one inquired, seeking to discern the impact of Trump's words.

Asked if anyone from the administration would resign over the President's remarks, a senior White House official quipped: "Good question."

None wholeheartedly defended what the President said, with only one suggesting the President's remarks were simply his interpretation of how the meeting went.

Rebukes at home

As Air Force One jetted westward toward Washington, there were few back in the capital willing to publicly defend the President's actions earlier in the day. Instead, Democrats and a sizable group of Republicans spoke out against him, rebuking his statements casting doubt on US intelligence agencies' assessments on Russian election interference. Members of Congress responded with howls of outrage, including from an expected collection of Republicans who have previously spoken out against the President.

"One of the most disgraceful performances by an American president in memory," was Sen. John McCain's description of the news conference.

"I did not think this was a good moment for our country," was the response from Sen. Bob Corker, the Republican chairman of the Senate Foreign Relations Committee who despondently spoke to reporters in a Capitol Hill basement.

"This is shameful," said Sen. Jeff Flake, a Republican who, like Corker, decided against seeking re-election this year.

In Washington, the only Republican -- indeed, the only politician at all -- who seemed enamored with Trump's performance was Vice President Mike Pence, a stalwart proponent of the President's who has rarely let slip a word of disagreement.

"Disagreements between our countries were discussed at length, and what the world saw, and the American people saw, is that President Donald Trump will always put the prosperity and security of America first," Pence said in remarks at the Commerce Department.

Damage control?

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Taken aback by the criticism, the President began trying to reframe the discussion in tweets aboard Air Force One. Yet his message was still a mixed one, far from fully supportive of the US intelligence community's assessment about Russia election interference. He did not repeat those denials, but argued it was more important to look forward.

"In order to build a brighter future, we cannot exclusively focus on the past -- as the world's two largest nuclear powers, we must get along!" he wrote.

As I said today and many times before, "I have GREAT confidence in MY intelligence people." However, I also recognize that in order to build a brighter future, we cannot exclusively focus on the past -- as the world's two largest nuclear powers, we must get along! #HELSINKI2018 — Donald J. Trump (@realDonaldTrump) July 16, 2018

Privately, however, there was little crowing after Trump's news conference. Instead, aides wondered whether the summit was a mistake from the start, even after Trump insisted repeatedly it be arranged over a matter of months.

Spending the weekend at his golf resort in Scotland, Trump underwent brief preparatory sessions with aides who tagged along to the Scottish coast lugging briefing binders and topic papers, most of which went unseen by the President himself.

Instead, Trump's aides -- including Chief of Staff John Kelly and National Security Adviser John Bolton -- presented him short talking points they hoped would narrow his focus ahead of the high-stakes encounter, including on Syria, Ukraine and election interference. Before he left for Europe, Trump indicated to aides that he would raise the issue, even if he expected little to come from the conversation beyond Putin's rote denials.

Even after he was briefed last week by Deputy Attorney General Rod Rosenstein about pending indictments of Russian government agents linked to the cyber-interference, Trump maintained he would raise the meddling with Putin. He did not request the Justice Department delay the announcement of the indictments until after the Helsinki summit, asking instead they be made public before he arrived in the Finnish capital.

In talking points sent to surrogates late Sunday night, the White House instructed its allies to argue Russia has already faced consequences for meddling in the 2016 election and cited the special counsel's indictment of Russians for their alleged hacking as one of the top ways the Trump administration has been tough on Russia.

"President Trump will continue to hold Russia responsible for its behavior in the United States and around the world," the talking points read. "Russia must stay out of US elections, they have already faced repercussions and will continue to if their behavior continues."

In public remarks and briefings, top administration officials declined to identify any particular outcome the President was seeking in Helsinki. Instead, they suggested the summit be interpreted less for what it achieved than what it was: two leaders meeting face-to-face with the goal of reversing a long-soured bilateral relationship.

Seeking positive momentum

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Trump encouraged his advisers to plan a summit that would highlight his perceived deal-making prowess, hoping to capture some of the media attention that followed him to Singapore last month, where he met for historic talks with North Korean leader Kim Jong Un.

The President declared that event an unmitigated success, despite evidence Pyongyang is continuing to develop its nuclear program. In conversations with confidants, Trump has marveled at the amount of television coverage the Singapore summit garnered, and suggested his encounter with Putin could match or even exceed it.

In talks with Russian officials, the White House passed along Trump's request for a one-on-one session with Putin, something he believed could better foster leader-to-leader ties. An official involved in the planning said Trump also expressed a belief that a private meeting with Putin would reduce the potential for leaks and disallow aides who might take a harder line on Russia from undercutting him.

That led to concerns among officials that no official record of the meeting would exist, aside from Trump's own recollections. When the two men sat before cameras at the start of the session, a pen and notepad was positioned next to Putin -- but not next to Trump.

Afterward, a US official said the translator in Trump's one-on-one with Putin would likely be debriefed, at least informally, by other US officials about some of what took place in the meeting -- not unusual practice for one-on-one meetings, according to the official, though the contents of that nearly two-hour meeting have gained additional scrutiny following Trump's extraordinary remarks.