DENVER: Timothy McVeigh entered the courtroom for closing arguments in the Oklahoma City bombing trial smiling and confident, much the same as he has throughout the trial. But his mood soon turned sour, the defendant clasping his hands over his face as prosecutor Larry Mackey carefully reviewed the government's case against him. He said McVeigh's own writings and the anti-government literature found in his possession showed that he was motivated by rage over the deadly 1993 federal siege at Waco. Most damning, Mackey noted, was the fact that McVeigh just happened to be arrested 75 miles from the bomb scene carrying literature announcing his intent, with explosives residue on his clothing. "Tim McVeigh is either guilty," Mackey told jurors, "or he's the unluckiest man in America." Mackey's return to the powerful testimony of Helena Garrett, who lost her young son Tevin in the bombing, brought tears to a few jurors. ''He died. This bomber didn't care. The only thing he cared about was bringing down the Murrah building on top of its occupants.'' Though defense attorney Stephen Jones asked jurors not to base their decisions on emotional appeals from the prosecution, it is hard to see how they can separate emotion from their consideration of the guilt or innocence of the man accused of the most heinous act of terrorism ever committed on U.S. soil. They are expected to begin deliberations on Friday.