IN a sense, the Iran-contra affair and the criminal prosecutions arising out of it seem out of sync. The affair itself involved two of the hottest foreign policy issues of the '80s: United States relations with the Ayatollah Khomeini's Iran and its hostage-taking affiliates, and US backing for the Nicaraguan contras. American arms secretly flowed to both Iran and the contras and millions of dollars circulated through hidden channels, all orchestrated from a few small offices in the Reagan White House.
Yet these vivid events are just a muted backdrop for the prosecutions by Independent Counsel Lawrence Walsh. Most of the charges against the seven men who have pleaded guilty or been convicted in the affair - most recently, former national security adviser John Poindexter - have dealt only with attempts by Reagan-administration officials to hide their actions from Congress.
The disproportionality has led some to belittle Mr. Walsh's efforts as a Congress-inspired vendetta and a waste of public funds.
To be sure, the course of Walsh's prosecutions has demonstrated the limitations of the criminal-justice system - especially when national-security considerations, real or purported, seal so much evidence and block so many avenues of investigation.
But Saturday's conviction of Mr. Poindexter on five coverup charges reminds us that the Iran-contra affair wasn't just about differences over foreign policy. It was also about relations - and trust - between Congress and the White House. The president's men didn't just disagree with Congress: They took it upon themselves to defy Congress, and this required misleading the lawmakers and obstructing justice.
They not only held themselves above the law, but they also - like the Watergate conspirators - did incalculable harm to a governmental relationship on which the public's business depends.
The executive and legislative branches will frequently clash, for reasons built into our balance-of-powers system. But the differences must be negotiated into public policy with honesty, fairness, and good will, or distrust will become sand in the gears of government. Poindexter, North, McFarlane et al. lost sight of this.