There should be no question now that Russia interfered in last year’s election on behalf of Donald Trump, and that, despite vehement and self-righteous denials, the Trump campaign was fully aware.

The counterargument built atop a year’s worth of lies and cries of “fake news” collapsed Tuesday under the weight of hard facts. Emails show Donald Trump Jr. and two other high-ranking members of the Trump campaign were told in no uncertain terms that the Kremlin supported their candidate and had information damaging to their opponent, Hillary Clinton. Rather than call the authorities — as campaigns have done before in such situations, and as is required by patriotism and, perhaps, the law — they eagerly set up a meeting.

At very least, this indicates that the campaign was open to receiving information damaging to Clinton from a foreign power hostile to the United States, and that the denials and constant complaints that the investigation into the Russian meddling is nothing more than a “witch hunt” were themselves outright lies.

It also raises questions about whether the meeting described in the emails was the only one of its kind, or whether it was just the beginning at some level of a cooperative enterprise that also included the Russian government’s hacking and release of emails from top Democratic officials and targeted dissemination of false “news” stories.

For one thing, it is absurd to think that then-candidate Donald Trump was not made aware of the opportunity to smear Clinton, putting the lie to the president’s claims that “nobody really knows” if Russia interfered in the election, and making even more worrisome his attempts to limit the FBI’s investigation into the matter.

On an appearance Tuesday night on Fox News Channel, Trump Jr. downplayed the importance of the meeting, saying it produced nothing worth passing on to his father. But how can anyone possibly believe him now?

Last year and again in March, Trump Jr. angrily denied meeting with Russian representatives, calling such reports “phony” and “disgusting.” When first confronted by the New York Times about the meeting with the Russian lawyer, he said it was only about the adoption by Americans of Russian babies. Then, he conceded it was about information that may be helpful to the campaign, but that he wasn’t told who the meeting would be with.

On Tuesday, however, with the Times ready to release the emails, Trump Jr. tweeted them out himself, revealing nearly every word he had said in his defense to be a lie or minimization.

The subject line of the emails was “Russia — Clinton — private and confidential.” He was told by the friend setting up the meeting — someone with close connections to Russian President Vladimir Putin — that it would be with a “Russian government lawyer” on behalf of “Russia and its government’s support” for candidate Trump, with information to “incriminate Hillary.” Trump Jr. replied, “I love it.”

The email chain was forwarded to Paul Manafort, then the campaign chairman, and Jared Kushner, the president’s son-in-law and now a senior White House adviser, both of whom also attended the meeting.

At each point in the story’s development, Trump Jr. lied, misled, and grandstanded, only copping to information the Times had independently verified, just as other Trump administration officials have handled their contacts with Russian officials.

Which makes us wonder what else they aren’t saying. The only question now is, as Sen. Angus King said Tuesday on MSNBC, “Is this the tip of an information iceberg, or is this an isolated event?”