Washington ? The chairman of the military Joint Chiefs of Staff and the prosecutor handling charges against suspected Sept. 11 terrorists in Germany will testify next week in the final hearing of the commission investigating the attacks.

The hearing next Wednesday and Thursday will track the development of the plot from its origins in the 1990s. On the second day, the 10-member panel will review the national emergency response by the Federal Aviation Administration and U.S. air defenses on the day of the attacks.

Among the questions the panel wants answered: What was the federal government’s protocol for responding to the Sept. 11 attacks? How well did the government perform that day? Are federal officials now ready in the event of future attacks?

“We will attempt to close the circle,” said Thomas Kean, the commission’s Republican chairman. “We will look back to the roots and growth of al-Qaida, its previous attacks on the United States, its financing and international support, and how it plotted such detailed and intricate attacks on our soil.”

“The commission will then turn again to the day of Sept. 11, 2001, to examine how the federal government learned of and responded to the attacks,” he said in a statement.

Scheduled to testify in addition to Gen. Richard Myers, chairman of the Joint Chiefs, are top law enforcement and intelligence experts on al-Qaida, including Matthias Krauss, who is handling the prosecution of the al-Qaida cell in Hamburg, Germany, that was key to the hijacking plot.