By the end of that September, Khalifi was no longer speaking in "nebulous" terms, the FBI agent said. He was doing research on the Internet to justify his desire to engage in jihad overseas and was willing to die for the cause in Afghanistan or for the Palestinians.
Khalifi next told Hussien that he wanted weapons training and had his eye on attacking an office building in Alexandria, Va., that he thought housed military offices. The news concerned FBI officials, who ramped up surveillance of Khalifi to ensure that he didn't try to launch an attack on his own and without the knowledge of undercover agents.
In December, Hussien took Khalifi to a comrade in Baltimore, a person the undercover agent promised could help in his quest for jihad. The other man, who called himself "Yussef," was also an FBI agent. During the encounter, the men handled an AK-47, and Khalifi discussed his desire to shoot someone at the office building or to blow it up.
A week later, Khalifi started talking about attacking a synagogue or killing a U.S. Army general leaving his house. Then he wanted to leave a bomb at Aria Pizzeria, a restaurant at the Ronald Reagan Building in downtown Washington. He and Hussien ate lunch at the spot, where Hussien told Khalifi that he and Yussef were members of al-Qaida.
At nearly every meeting, FBI agents said, Hussien asked Khalifi whether he was sure he wanted to launch an attack and whether there was a more peaceful way to engage in jihad than killing people. In past investigations, other suspects have walked away from similar plots and not been charged, FBI officials said.
At one point, Khalifi became so frustrated by the questions that he told the undercover agent to "stop asking him if he wanted to do this," the case's lead agent said.