MIAMI, Aug. 16 — In a major victory for the Bush administration, a federal jury here found Jose Padilla guilty on terrorism conspiracy charges Thursday after little more than a day of deliberations.

Mr. Padilla, one of the first Americans to be named an “enemy combatant” in the tense months after Sept. 11, 2001, now faces life in prison. He was released from an unprecedented military detention without charges last year, only to face criminal charges in federal court here. The government’s chief evidence was an application form that government prosecutors said Mr. Padilla, 36, filled out to attend an Al Qaeda training camp in Afghanistan in 2000.

Mr. Padilla’s extraordinary legal journey began in May 2002, when he was arrested at Chicago’s O’Hare Airport and taken into military custody. Attorney General John Ashcroft announced Mr. Padilla’s capture a month later in a special news conference from Moscow, saying that an “unfolding terrorist plot to attack the United States by exploding a radioactive dirty bomb” had been disrupted, an attack with the potential to cause “mass death and injury.”

He was held in isolation on a military brig in South Carolina for more than three years, and was transferred to civilian custody last year only after the Supreme Court considered taking up the case. Mr. Padilla’s lawyers tried in vain to have him found incompetent to stand trial on grounds that he was tortured in the brig. The government said he was never mistreated.

The dirty bomb allegations that made Mr. Padilla a high-profile terror suspect in 2002 were not part of the case here. Instead, Mr. Padilla and two co-defendants of Arab descent were charged with conspiring to murder, kidnap and maim people overseas.

A prosecutor described one of Mr. Padilla’s two co-defendants, Adham Hassoun, as a zealot who “indoctrinated people and converted them to become Al Qaeda fighters,” and the other, Kifah Jayyousi, as “the money man” who provided financing and equipment to terrorist groups overseas.

One piece of evidence entered in the trial was an application that prosecutors maintained that Mr. Padilla had filled out — in Arabic, under an alias — to attend a terrorist training camp. Another block of evidence came from tapes of the defendants’ phone conversations, thousands of which were recorded by the F.B.I. from 1993 to 2000.

Defense lawyers had contended that their clients were merely passionate and vocal Muslims with no connection to Al Qaeda and no intent to support terrorism. The government’s case was politically motivated, they said, and was fueled by the nation’s dread after the Sept. 11 attacks.

Jeanne Baker, a lawyer for Mr. Hassoun, and other defense lawyers said that in fact their clients had only been trying to help Muslims who were under attack in the 1990s in places like Kosovo and Chechnya. In that context, Ms. Baker said, words like mujahedeen and jihad have positive connotations and nothing to do with terrorism.

Anthony Natale, a lawyer for Mr. Padilla, said, “In this case, you will see how in the absence of hard evidence, a suspicion can be fueled by fear, nourished by prejudice and directed by politics into a criminal prosecution.”

Mr. Padilla, now 36, made his first visit to a Muslim country, Egypt, in 1998. He did so only because he wanted to become an imam, said Mr. Natale, who, like the other defense lawyers, dismissed the government’s accusation of a conspiracy to “murder, kidnap and maim” people overseas. “As you will hear clearly and without a doubt,” he said, “there were no victims in this case, real or imagined.”