The capture last week of Suleiman Abu Ghaith, Osama bin Laden's son-in-law and an al Quaida spokesman, was another in a series of incremental victories in the fight against the terrorist organization.

Mr. Abu Ghaith had appeared in videos with bin Laden following the Sept. 11, 2001 terrorist attacks, and had exhorted radical Islamists to carry out attacks on the United States.

He was arrested in Jordan after being deported from Turkey, in an operation that featured great cooperation by the FBI and the CIA.

He was taken to New York rather than to the detention camp at Guantanamo Bay, Cuba, and arraigned in federal court on charges of criminal conspiracy to murder Americans.

Some in Congress complained that the suspect should have been taken to Guantanamo and tried in the military tribunal system. But the tribunals are charged with prosecuting internationally recognized war crimes, which do not include criminal conspiracy, a federal felony.

Mr. Suleiman Abu Ghaith will be tried in the U.S. District Court for the Southern District of New York, Manhattan. Despite the noise about the supposed inability of civilian federal courts to deal effectively with terrorism-related cases, the Southern District has handled dozens of such trials, beginning with those resulting from the initial terrorist attack on the World Trade Center in 1993.

Lawmakers should embrace the trials in civilian courts because the justice system is one of the great institutions that separate us from the extremists. Let the world see true U.S. justice as it unfolds.