More than any congressional investigation, the guilty verdict in the trial of Lewis “Scooter” Libby, chief aide to Vice President Dick Cheney, reveals what the White House was willing to do and say to shape public opinion about the invasion of Iraq. The verdict’s power is not in its surprise but in its dismaying predictability.

“Any lie under oath is serious,” said prosecutor, Patrick J. Fitzgerald, after the trial. This case was about lies to cover the exposure of earlier lies, whether under oath or not.

Mr. Fitzgerald’s skilled and dogged investigation built a case that found Mr. Libby accused of repeatedly lying about his knowledge of Valerie Plame Wilson and how he learned about her role as a CIA spy. Mr. Libby committed these crimes after tying to discredit Mrs. Wilson’s husband, former diplomat Joseph Wilson, who had investigated and disputed one of the administration’s reasons for seeking to attack Iraq. A jury found Mr. Libby guilty of obstructing justice, making false statements to the FBI and committing perjury before a grand jury.

It is presidential boilerplate to explain the grave nature of taking a nation to war, but the gravity of the decision is present in every step taken toward firing the first shot. To lash out at those who have responsibly disputed a case for war is to show disregard for the ones asked to risk their lives in its pursuit. What the jury’s decision powerfully concludes this week in the Libby case is that a high-ranking official showed exactly that disregard.

Everything about Mr. Libby’s service to Vice President Cheney suggests he was a loyal, diligent and careful man. No one knows for certain whether he engaged on his own in discrediting Mr. Wilson, who printed his doubts unequivocally in a 2003 Op-Ed piece in the New York Times, or whether he was assigned the duty. Other officials, notably Richard Armitage, but also Karl Rove, according to testimony, leaked information about Mrs. Wilson. A civil case brought by the Wilsons may reveal more about their roles, and the role of the vice president, whose handwritten notes on the issue were important pieces of evidence.

The Libby case repeats a pattern of political intimidation. Whether Rovian campaign tactics, silencing federal scientists looking into climate change, attacking members of Congress who have disagreed with the White House about the war, or, perhaps, firing U.S. attorneys who were involved in politically sensitive prosecutions, the stomping of dissent is similar.

But bullying the truth doesn’t make it false, as the events in Iraq showed from early in the war. Mr. Libby’s crime did not begin with his attempted intimidation of the Wilsons; it started with a White House that sees all opposition as its enemy. Mr. Libby was found guilty because he misunderstood where those attacks ended and the justice system began.