A prudent president, facing multiple battles on legislative and other priorities that are crucial to his first-year success, would find ways to avoid needless controversy. Not President Trump. He’s doing exactly the opposite, and the credibility gap continues to grow.

The House Republican leadership’s proposal to repeal and replace the Affordable Care Act, which Trump has embraced, faces serious opposition within the party. The president’s newly proposed budget, which would slash domestic discretionary spending, the State Department and the Environmental Protection Agency, has been met with stiff resistance, even among some Republicans. The administration’s second attempt to impose a travel ban is on hold, once again caught up in the courts.

Meanwhile, Trump will not let go of his claim that former president Barack Obama tapped his phones at Trump Tower during the election, despite no supporting evidence. The president has been offered numerous exit ramps to put this self-created controversy behind him. Instead, he remains stubbornly defiant, perpetuating rather than closing a damaging chapter in his presidency that in the past few days became an international embarrassment.

The latest illustration of the president’s incapacity to admit error came Friday at a joint news conference with German Chancellor Angela Merkel. He was asked by German reporter Ansgar Graw of Die Welt about the angry denial by British officials that Britain, at the behest of the Obama administration, had spied on Trump during the presidential campaign.

“Do you think it was a mistake to blame British intelligence for this?” the president was asked. White House press secretary Sean Spicer had pointed to an unverified report about British intelligence a day earlier. Trump began his answer with what he hoped would be a lighthearted comment, but one nonetheless that suggested he didn’t believe the British.

(Reuters)

Gesturing toward Merkel, he said, “As far as wiretapping, I guess, by this past administration, at least we have something in common, perhaps.” The president was referring to reports that the National Security Agency had listened in on the German chancellery during Obama’s presidency.

Despite laughter in the East Room, Merkel appeared to find no humor in Trump’s response, offering a look that charitably could be called one of puzzlement that the leader of the world’s most powerful country would try to drag her into his controversy.

[Trump drags allies into the controversy over unproven claims]

Trump might have stopped there, but he plunged ahead. “And just to finish your question,” he told the German reporter, “we said nothing. All we did was quote a certain very talented legal mind who was the one responsible for saying that on television. I didn’t make an opinion on it. That was a statement made by a very talented lawyer on Fox. And so you shouldn’t be talking to me, you should be talking to Fox, okay?”

With that response, Trump was following a playbook that has become standard for his White House, which is to duck, deflect and in all other ways do everything but acknowledge that there is no credible evidence for Trump’s original claim, tweeted out a few weeks ago. Having made the allegation, the president has asked others to prove it. When the evidence points in the opposite direction, the White House prefers to look for questionable ways to support what Trump claimed.

That was the case with Trump’s words Friday. The “talented lawyer” to whom the president was referring was Andrew Napolitano, a former New Jersey Superior Court judge now working as a Fox News commentator. Napolitano was the originator of the assertion about the British role in the surveillance of Trump, basing what he said on three intelligence sources.

Spicer had cited Napolitano as he tried to defend his boss during an aggressively combative exchange with reporters Thursday. This is the same White House that has previously attacked accurate news stories that included the use of unnamed sources as fake news.

(Bastien Inzaurralde/The Washington Post)

Spicer’s comments drew a swift and rare public rebuke from British intelligence, which called the claim “utterly ridiculous.” The dust up clearly strained tensions between the White House and America’s closest ally. Meanwhile, Fox News declined to stand behind Napolitano’s claims, noting Friday that its news team has found no evidence to support what the judge had said. That’s one more case in which the White House has gone looking for a lifeline without success.

Day by day, the White House defense of Trump has been weakened, as one after another official has walked away from the president’s tweets about Obama. The four leaders of the House and Senate intelligence committees have said they have seen no such evidence. FBI Director James B. Comey let it be known almost instantly two weeks ago that there was nothing to the claim.

Other elected officials, including Republicans, have demanded that the administration provide evidence. One Republican, Rep. Tom Cole (Okla.), said Friday that the president should apologize to Obama.

[House Intelligence Committee receives DOJ documents on wiretap claim]

In the face of this, Trump had nothing to say until pressed twice by German reporters, to their credit, at Friday’s session with Merkel. Spicer has been thrust into the role of leading the defense at the risk of his credibility. He has sought to redefine the English language by suggesting Trump’s words did not mean what the words meant, hoping to take some of the sting out of the implication in Trump’s tweets that Obama had broken the law by ordering surveillance on Trump.

This chapter could come to an end this week. Comey is scheduled to testify Monday in an open session before the House Intelligence Committee about Russian hacking in the election and related matters. He will certainly be asked directly about Trump’s allegation against Obama.

The Russia investigation on Capitol Hill remains open and vitally important. That the Russians meddled in the election is not disputed, given the weight of the intelligence community’s findings. But much more needs to be known, and at this point, that responsibility falls to Congress.

One key aspect of that investigation is whether the Trump campaign or its close allies were in collusion with the Russians. That there were contacts between Trump officials and Russians also is not in dispute. Attorney General Jeff Sessions has acknowledged that he met with the Russian ambassador last fall, for example.

What is in dispute is whether those contacts were ordinary and legitimate, as the Sessions meeting was, or whether there were contacts between various Trump advisers and Russians that amounted to participation in a scheme to harm Hillary Clinton’s campaign and thereby help Trump.

James R. Clapper Jr., the former director of national intelligence, said earlier this month on NBC’s “Meet the Press,” that, at the time he left office in January, he had seen no evidence of collusion between the Trump team and the Russians. Spicer was particularly irritated Thursday that this fact has gotten far less attention than Trump’s tweets about Obama as he repeatedly chided reporters during the briefing.

If Comey shoots down Trump’s allegation about Obama illegally ordering surveillance on Trump Tower, how will Trump respond? In other words, what kind of proof, evidence or testimony would satisfy him that what he said took place did not take place?

Based on his performance Friday, he’s not prepared to accept the word of those who should know. If he’s doubling down in the face of outright denial from the British intelligence community about a claim he saw on Fox News, whose testimony here would satisfy him? And what will his defenders say then? This week should provide the answer to that, at least.