We know that the Russian government interfered repeatedly in the 2016 presidential election, by hacking into computer servers of the Democratic National Committee and the Clinton campaign. We know that it did this with the goals of dividing Americans and helping Donald Trump win the presidency. We know that when top members of the Trump campaign learned about this interference, they didn’t just fail to report it to the F.B.I. They welcomed it. They encouraged it. They made jokes about it. On the same day that Mr. Trump publicly urged the Russians to hack into Hillary Clinton’s emails, they began to do just that. And we know that when questioned by federal authorities, many of Mr. Trump’s top associates lied, sometimes repeatedly, about their communications with Russians. None of this is in dispute.

That Mr. Mueller couldn’t find sufficient evidence that Mr. Trump or anyone involved in his campaign had coordinated directly with the Russians may be explained by the fact that they didn’t need to. They were already getting that help.

We also know that what began as a counterintelligence investigation quickly turned into a criminal investigation, in large part because Mr. Trump surrounded himself with criminals. To date, his campaign chairman, Paul Manafort; his deputy campaign chairman, Rick Gates; his national security adviser, Michael Flynn; his campaign foreign policy adviser, George Papadopoulos; and his personal lawyer and fixer, Michael Cohen, have all pleaded guilty or been convicted of federal crimes. In January, Mr. Mueller charged Roger Stone, Mr. Trump’s longtime aide, with multiple counts of witness tampering, obstructing justice, and making false statements.

Imagine if we’d learned all of this just Sunday, in one fell swoop, rather than in a trickle of indictments and prosecutions over the last 18 months.

Americans are, of course, continuing to learn more unsettling truths from the dozen or so other investigations that are continuing, such as the one in New York that has already landed Mr. Cohen a three-year prison sentence for campaign-finance violations that prosecutors said Mr. Trump was also involved in, from the White House.

One might expect Mr. Trump to feel happiness at Sunday’s news, but for him, that emotion seems to transform into a desire for vengeance. It’s no surprise that he and his allies are once again floating the idea of prosecuting Mrs. Clinton. Remember her? She was the candidate who, during a presidential debate all the way back in 2016, said: “It’s pretty clear you won’t admit that the Russians have engaged in cyberattacks against the United States of America, that you encouraged espionage against our people, that you are willing to spout the Putin line, sign up for his wish list, break up NATO, do whatever he wants to do and that you continue to get help from him because he has a very clear favorite in this race.”

Mr. Putin did have a clear favorite. He interfered on his behalf, and his favorite was elected president. Trump campaign officials knew about this and were more than happy for the help. Then they lied about receiving that help. This isn’t so complicated. And while Mr. Mueller may not be able to do anything about it, Congress, and the American people, certainly can.