When federal prosecutors earlier this week announced a plea deal that will ultimately deport the controversial former University of South Florida computer science professor Sami Al-Arian, they hailed it as a major achievement in the war on terror. As U.S. Attorney Paul Perez put it in a statement, “Because of the painstaking work of the prosecutors and agents who pursued this case, Al-Arian has now confessed to helping terrorists do their work from his base here in the United States — a base he is no longer able to maintain.” But given all the buildup, the resolution of the Al-Arian case seems far from a clear-cut victory, and the government’s triumphant tone speaks volumes about its less-than-stellar record in federal anti-terror cases.

After all, the U.S. government seemed to enjoy every advantage in the prosecution of Al-Arian — who was accused in 2003 of conspiring with the terrorist group Palestinian Islamic Jihad. It had thousands of hours of taped phone calls, intercepted throughout a dozen years of surveillance; emotionally wrenching testimony from witnesses, including the father of an American girl murdered in Israel by a PIJ suicide bomber; and a jittery public anxious for convictions in the war on terror.

Still, in December, after a six-month trial, a skeptical Tampa jury delivered not one single guilty verdict from the 53-count indictment charging Al-Arian and three other men with terrorist activities. Al-Arian — whom the Bush Administration had even tagged as PIJ’s North American leader — was acquitted on eight of 17 counts. The jury deadlocked on the remaining counts against him, but jurors later indicated to reporters that most of them had favored acquittal on those charges as well. The government, they said, simply wasn’t able to establish a clear link between Al-Arian’s constitutionally protected freedom to express support for the PIJ and the group’s violent acts half a world away. It was one of the Justice Department’s most embarrassing legal setbacks since 9/11.

Frustrated prosecutors, not surprisingly, weren’t willing to admit defeat. So to spare his family the emotional havoc of a retrial, Al-Arian cut a deal. After months of negotiations, the Feds announced this week that the USF professor had pleaded guilty to one count of conspiracy to provide services to the PIJ, such as immigration assistance to its members and lying about a former associate’s affiliation with the terrorist group. A sentencing hearing is scheduled for May 1. But though guidelines call for 46 to 57 months in prison, Al-Arian, who was born in Kuwait and has some family in Egypt, will serve only a fraction of that time and then be deported to an as yet undetermined country.

Because it couldn’t prove Al-Arian was “the most powerful man” in the Palestinian Islamic Jihad, as one prosecutor characterized him during the trial, or link him directly with any of the brutal killings perpetrated by PIJ, “this [was] a failed prosecution, period,” Al-Arian attorney Linda Moreno tells TIME. “[Former Attorney General] John Ashcroft announced the indictment three years ago on the steps of the Justice Department. Three years later, we have the Department of Justice recommending that Dr. Al-Arian be sentenced to the lowest term possible and agreeing that this is not a crime of violence that he’s pleading to. This is hardly a victory for the prosecution.”