Was Russia's effort to interfere in the 2016 election the most important issue on the table at President Trump's Helsinki summit with President Vladimir Putin? No. But it's not an unimportant issue either, and Trump knew the American press is obsessed with it. So he knew it would play a big role in the Trump-Putin post-summit news conference.

There are all sorts of aspects to the Trump-Russia affair, but in light of special counsel Robert Mueller's decision to indict 12 Russian intelligence agents on Friday before the Monday summit, the president also knew reporters would want to hear him specifically affirm Mueller's allegation that the Russian agents hacked the Democratic Party and Hillary Clinton campaign.

It wouldn't be hard for the president to do. After all, the House Intelligence Committee, chaired by Trump supporter Rep. Devin Nunes, along with the Senate Intelligence Committee, the Intelligence Community, and Mueller have all concluded that Russia attempted to disrupt the election. None of them has proved, or even alleged, that the Russian effort affected a single vote. But there is a consensus that there was a Russian effort.

So to put it in crass terms, Trump could easily have given the press what it wanted, which would probably have given him room to pay attention to issues like arms control, Syria, China, trade, and Crimea.

But no. That's not how Trump handles the Trump-Russia affair. And so, when he was asked a simple, straightforward question — U.S. intelligence agencies say Russia interfered. Putin denies it. Who do you believe? — Trump would not give a simple, straightforward answer.

Instead, he started with misdirection. "You have groups that are wondering why the FBI never took the server," he said. "Why haven't they taken the server? Why was the FBI told to leave the office of the Democratic National Committee? I've been wondering that."

Then Trump said his top intelligence officials came to him and "said they think it's Russia," meaning they believe Russia was behind the hacks. On the other hand, Trump said, "I have President Putin; he just said it's not Russia." Trump cast doubt on the U.S. agencies' conclusion: "I don't see any reason why it would be [Russia]," he said, "but I really do want to see the server." And finally: "So I have great confidence in my intelligence people, but I will tell you that President Putin was extremely strong and powerful in his denial today."

The bottom line was that Trump, the president of the United States, would not accept the U.S. government's assessment of the Russian effort and hinted that he had at least as much or more faith in Putin's version of events.

Predictably, all hell broke out, with anti-Trump commentators talking treason and Trump supporters in Congress declining to defend the president. The controversy consumed cable TV and was sure to last until the next controversy begins. And Trump could have avoided it all.

So why did he do what he did? The answer has to do with the peculiar nature of the Russia investigation, and the peculiar nature of Donald Trump.

There have always been two parts to the Trump-Russia probe: the what-Russia-did part, which is the investigation into Russia's actions during the campaign, and the get-Trump part, which is the effort to use the investigation to remove him from office.

Trump's problem is that he has always refused, or been unable, to separate the two. One is about national security and international relations, while the other is about Donald Trump.

The president clearly believes if he gives an inch on the what-Russia-did part — if he concedes that Russia made an effort to disrupt the election — his adversaries, who want to discredit his election, undermine him, and force him from office, will take a mile on the get-Trump part. That's consistent with how Trump approaches other problems; he doesn't admit anything, because he knows his adversaries will never be satisfied and just demand more.

But Trump's approach doesn't work for the Trump-Russia probe. There's no reason he could not accept the verdicts of the House Intelligence Committee, the Senate Intelligence Committee, the Intelligence Community, and, yes, Mueller, that Russia tried to interfere in the election. There would be no political loss, and, in fact, great political gain, for Trump to endorse that finding.

At the same time, there is nothing wrong with Trump fighting back hard against the get-Trump part of the investigation. Voters know that Democrats, Resistance, and NeverTrump activists have accused Trump of collusion for two years and never proven their case. Mueller has charged lots of people with crimes, but none has involved collusion. That could still change — no one should claim to know what is coming next from Mueller — but Trump, as a matter of his own defense, is justified in repeating the "no collusion" and "witch hunt" mantras.

So in response to the "Who do you believe?" question in Helsinki, Trump could simply have said: I believe the House Intelligence Committee, the Senate Intelligence Committee, and the Intelligence Community. I believe the verdict of U.S. agencies. Russia did it. We've retaliated and we'll do more. But my adversaries at home have turned this into a politically motivated crusade to cripple the president of the United States, and it's time to stop it. Now, let's talk about issues that are vital for the future of America and the world.

Hours after the news conference, the White House sent out a fact sheet noting that Trump "has repeatedly said he believes the intelligence agencies when they said Russia interfered in American elections." Among those times, according to the White House: In January 2017, Trump said, "I think it was Russia." He said precisely the same thing again in July 2017. In November 2017, he said, "I'm with our agencies." And in March of this year, he said, "certainly there was meddling."

On some of those occasions, Trump conceded the Russian effort (in minimal fashion) only after initially denying it, or casting doubt on it, and coming under the same sort of media pressure he is under today. Now, he's likely to have to do it again.