David Jackson

USA TODAY

WASHINGTON – This was not what the White House wanted.

Nearly 90 minutes after the Justice Department announced it was appointing Robert Mueller to be special counsel to oversee the Russia investigation into possible collusion between the Trump campaign and his associates, the news stunned White House aides who scrambled to figure out the way forward.

A special counsel was a step Trump has vehemently opposed for all four months of his administration. Aides raced in and out of offices further inside the West Wing, carrying papers and working on an official response, ignoring questions from reporters lined up in the hallway outside Press Secretary Sean Spicer's office waiting for answers. "We'll have to get back to you," one aide shouted in the direction of the media.

As members of Capitol Hill started to comment on the Mueller appointment Wednesday evening – with many on both sides of the aisle expressing their approval for the Justice Department's move – the White House wound up issuing a terse, three-sentence statement under President Trump's name.

"As I have stated many times, a thorough investigation will confirm what we already know – there was no collusion between my campaign and any foreign entity," Trump said in the statement. "I look forward to this matter concluding quickly."

As some aides at the White House wondered how a special counsel would shadow their tenure, Trump concluded the statement by saying: "In the meantime, I will never stop fighting for the people and the issues that matter most to the future of our country."

White House aides didn't get a heads-up from the Justice Department until less than an hour before the news became public – and after Deputy Attorney General Rod Rosenstein had already signed the order designating Mueller to lead the Russia probe.

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In fact, as the Justice Department prepared to announce its decision, Trump was busy on another Oval Office task: Interviewing potential FBI directors to replace Comey. News of the appointment jarred aides, who were left wondering how the investigation would play out, when it might end, or how it might reach into and affect the White House.

Just this past Monday, White House Press Secretary Sean Spicer noted that the Russia issue is already being investigated by "a House committee, a Senate committee, the FBI – I don't know why you need additional resources when you already have three entities."

Spicer has repeatedly pointed out that no one has specifically accused Trump or his top aides of any kind of involvement in Russian effort to influence last year's election, frequently invoking the mantra "there's no there, there."

Now a Mueller-led investigation could drag on for at least a year, and shadow much of Trump's presidential agenda.

The surprise announcement capped what had otherwise been a relatively quiet day for Trump on the investigative front, after a very busy few weeks dogged by multiplying scandals.

In something of a departure of his usual practice, Trump did not tweet about the day's previous bombshell news: Revelations that fired FBI Director James Comey kept notes from his February meeting with Trump that said the president asked him to drop an investigation into ex-national security adviser Michael Flynn. At the time, Flynn had already been fired over his contacts with Russia.

Speaking earlier in the day at the commencement of the U.S. Coast Guard Academy in New London, Conn., Trump did protest his media coverage, as he often does – "no politician in history, and I say this with great surety, has been treated worse or more unfairly," he said – but signaled he would continue to be aggressive in accomplishing his goals.

"Don't give in," Trump counseled the cadets. "Don't back down."

Trump has consistently said Democrats are pushing the Russia investigation and using it as an excuse to explain away their election loss in November. On May 8, Trump tweeted: "The Russia-Trump collusion story is a total hoax, when will this taxpayer funded charade end?"

Trump returned to the White House in mid-afternoon Wednesday to soon learn news he surely did not relish.