Harry Litman is the former United States attorney for the Western District of Pennsylvania and deputy assistant attorney general in the Department of Justice. He currently teaches constitutional law in the political science department of the University of California, San Diego and practices law at Constantine Cannon. The opinions expressed in this commentary are those of the author. View more opinion articles on CNN.

(CNN) As scandal-weary as we are, we all need to take a deep breath to confront the gravity of the allegations that special counsel Robert Mueller brought on Friday against 12 members of the GRU, the Russian Military Intelligence organization.

The stunning accusation, in a meticulously detailed complaint lays it out: Members of an enemy army engaged in a coordinated criminal enterprise to secretly sabotage an American presidential election. The attacks were sustained, professional and largely successful. It would appear to be the most nefarious attack by a foreign government on the United States since Pearl Harbor.

Harry Litman

Worse, the attacks allegedly involved United States citizens, including a Trump campaign insider. Paragraph 44 of the indictment spells out that the defendants communicated with a "person who was in regular contact with senior members of the presidential campaign of Donald J. Trump."

It's a safe bet that the person did not report this patently illegal meddling to the FBI. That a person close to the campaign was allegedly involved raises the prospect of the unraveling of a conspiracy eclipsing Watergate in its brazenness and damage to national interests. Whoever it is, though, this person or persons may well be a concrete link between the Trump campaign and the saboteurs in the Russian government.

This revelation should finally put an end to the ignorant droning of the President and his defenders that the Mueller probe is a "witch hunt" that has failed to find any evidence of "collusion" with the Trump campaign.

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