The sentencing comes five months after Aldawsari was convicted on one count of attempted use of a weapon of mass destruction.
Federal agents thwarted Aldawsari's plot to obtain a dangerous chemical needed to make a weapon of mass destruction in the spring of 2011.
According to evidence presented by federal prosecutors at trial, Aldawsari was trying to purchase phenol, the last of three chemicals needed to make a type of explosive called picric acid-- a chemical cousin to TNT.
On Tuesday, Aldwasari was ushered into a courtroom at the Federal Courthouse in Amarillo just before 9:00 a.m.
He wore a navy jumpsuit marked with 'Lubbock County Jail' that hung off of him. His hair was long and his face was covered with a beard.
Federal prosecutors asked the judge for permission to call a witness who would testify to just how powerful the explosive Aldawsari was trying to make would be.
Judge Donald E. Walter, who presided over the trial and sentenced Aldawsari on Tuesday, declined the prosecutor's request, saying he knew how powerful the bomb would have been.
Lead defense attorney Dan Cogdell spent about five minutes arguing for a sentenced of less than twenty years.
Cogdell told the judge other terrorists who had been convicted under similar circumstances were sentenced to shorter sentences.
Aldawsari's defense attorneys also tried to convince the judge that their client was depressed and felt like an outcast after transferring from Vanderbilt to Texas Tech University.
Jeffery Haag, who was the lead US prosecutor in the case, argued strongly for the life sentence, telling Judge Walter that Aldawsari is a threat to Americans both at home and abroad.
Judge Walter called Aldawsari to the stand to address the Court before being sentenced. As he stood in front of the judge, Aldawsari repeated over and over how sorry he was for what he had done.
"I'm sorry for these bad actions," Aldawsari said, "but in the end, those bad actions didn't cause harm to the US."
Judge Walter asked Aldawsari what happened in the convicted terrorists' life that led him to try and plot an attack.
Aldawsari told the judge he turned to jihadist videos as a way to feel close to home.
"I missed my family, my neighbors and my friends," he said quietly at the front of the courtroom.
After Aldawsari made his statement, the judge spent several minutes talking and handing down his rationale for reaching his sentence.
Amid several sighs and pauses for thought, Judge Walter finally told Aldawsari he could not forgive the magnitude of what the 20-year-old terrorist had tried to do.
"[The] bottom line is, but by the grace of God, people would be dead," Walter said. "In every step of the way it was you and you alone."
Aldawsari was ordered to life in prison and will not face the possibility of parole. Cogdell, his defense attorney, said the defense team was disappointed by the decision and was confident Aldawsari would appeal the decision.