Under pressure over the revelation of secret surveillance programs, the director of the National Security Agency is scheduled to appear before the House Intelligence Committee on Tuesday.
A committee aide described the testimony of Gen. Keith Alexander, who is both director of the NSA and head of U.S. Cyber Command at Fort Meade, as "an opportunity to discuss how the disclosed NSA programs protect Americans from terror attacks on US soil, and why the disclosure of that classified information aids our adversaries."
The hearing is open to the public and will be streamed online.
President Barack Obama on Monday described the telephone and Internet surveillance programs as "transparent." Obama and others say the programs, through which NSA gathers data on telephone calls and collects information on the Internet activity of foreigners outside of the United States, have been approved by a secret court and conducted under the law and with the full knowledge of Congress.
Details of the programs were revealed by James Snowden, a former Marylander who worked as a contractor to the NSA. Snowden, whose location is now unknown, has been hailed by some as a hero for his disclosures.
Only 49 percent of Americans now believe Obama is "honest and trustworthy," according to the results of a CNN/Orc Poll released on Monday. That's a 9-point drop from last month, and it's the first time in his presidency that the figure had fallen below 50 percent.
Also scheduled to appear before the committee are Deputy Attorney General James Cole, Deputy FBI Director Sean Joyce and Robert Litt, general counsel to the Office of the Director of National Intelligence.