What got him into hot water was repeating that mantra with Putin standing at his side.
Career politicians would have known better. Trump only knows how to be who he is and say what he thinks, regardless of who's standing at the other lectern.
It was hardly "treasonous" or "impeachable," as too many cable TV talking heads and Twitter commentators hysterically declared.
But it was a diplomatic blunder that unfortunately will detract from an otherwise appropriate outreach designed to lower tensions between superpowers.
And even in reversing his comments today, who knows what tomorrow will bring, if history is any guide.
Just as wrong as Trump's news conference performance was the insistence from some quarters that he should have travelled to Helsinki to publicly humiliate Putin, which would have been another example of meaningless political theater.
What Trump knows is that the endless attention on election interference (it used to be "collusion," but that's fading away) is connected not to real concern over the sovereignty of our democracy, but rather to the fact that the wrong candidate won. It's why he has trouble feigning outrage over it.
Foreign interference in our elections did not begin in 2016, but you can be forgiven if you don't know that. The media largely yawned about it in 2008 and 2012, but there were a few isolated stories.
In May 2013, Time magazine reported that in August 2011 the Obama campaign learned that "foreign nation-states were trying to gain access to the campaign's databases and social media accounts with extraordinarily sophisticated means."
The article added that the same was true for the Romney campaign, which was "under constant attack." The National Republican Congressional Committee was also later targeted.
While no one would confirm which foreign powers were suspects, "one Obama campaign staffer said she was warned about the threat from China in particular."
The story noted that similar efforts had been detected back in 2008 when "both the Obama and McCain campaigns were the victims of a sophisticated hack, believed by law enforcement to be tied to foreign governments. . . . Viewed in hindsight, the attacks present a disturbing picture of interference in core American political functions."
The article - written five years ago, mind you - added, "The revelation in the days following Obama's historic victory was largely overlooked, and it was just a taste of what was to follow."
Consider that last point - the hacks were "largely overlooked" in the wake of "Obama's historic victory." In other words, no big deal. The right candidate won in 2008.
No special counsel needed. No more ink or airtime wasted on the subject. No sanctions suggested.
The breadth and width of foreign interference will probably never be known, since there was no pressure for additional scrutiny, as happened in 2016.
But in 2016, Trump was, of course, the wrong winner, and his narrow, upset victory made Russian interference wall-to-wall news, all day, every day, which, in turn, made Russia's goal of sowing discord and distrust among Americans wildly successful.
A New York Times article earlier this year noted that career intelligence veterans were not overly alarmed at Russia's attacks in 2016.
Loch Johnson, a renowned intelligence scholar, told the New York Times that Russia's 2016 operation "was simply the cyber-age version" of what the United States itself has long done.
Johnson said, "We've been doing this kind of thing since the CIA was created in 1947. We've used posters, pamphlets, mailers, banners - you name it. We've planted false information in foreign newspapers. We've used what the British call 'King George's cavalry': suitcases of cash."
Everyone quantifies such admissions with a reminder that there is no "moral equivalency" - the US interferes in elections for the right reasons, and it's done to us for the wrong reasons.
But although Russian election interference in 2016 was quickly weaponised politically, even Trump's supporters sometimes wish he would just say the words that will make everyone happy.
But Trump seldom grants such small favours, and hysteria ensues. Calm will eventually be restored - until next time, which will no doubt arrive any day.
