Three hours before they handed down a sentence that could put an Oregon man in prison for life, deliberating jurors sent a note to a trial judge with a question.

Did the man whose fate they were deciding need to have envisioned the specific crime for which he was accused? Or did he merely need to be inclined toward some kind of terroristic act?

Their question more broadly reflects the central debate at the heart of the trial of Mohamed Mohamud, a 21-year-old Somali-American found guilty on Thursday of attempting to bomb a Portland Christmas tree-lighting in November 2010.

Prosecutors were met by a claim of entrapment by Mohamud's defense team, and needed to convince jurors that he was predisposed to terrorism by the time an FBI informant began discussing radical jihad with him over emails.

The judge, Garr King, told jurors Thursday that Mohamud only had to be likely to commit the offense or one like it, and he did not specifically have to be thinking about a bomb at the specific time and place at which he and two undercover FBI agents decided to plant one.

The bomb was a fake, supplied by the agents posing as jihadis.

Jurors were given starkly different portraits of the man who was 17 when the FBI began to focus on him. In the prosecution's description, Mohamud was a powder keg in search of a spark, an angry teenager with the right combination of anti-Western sentiment and a plausible cover story as an Oregon college student.