Senators from both parties may be on a collision course with the White House over its top national security nominations, because of concerns over the Obama administration's drone program.

A bipartisan group of 11 senators wrote a letter to President Obama Monday asking for "any and all legal opinions" that describe the basis for the authority to "deliberately kill American citizens."

The questions come in advance of CIA director nominee John Brennan's confirmation hearing Thursday before the Senate intelligence committee. Several of the authors of the drone letter sit on that committee. Obama's nominee for Defense secretary, Chuck Hagel, also had his confirmation hearing last week.

The letter Monday made a blunt threat suggesting that withholding information on drones could imperil those nominations.

"The executive branch's cooperation on this matter will help avoid an unnecessary confrontation that could affect the Senate's consideration of nominees for national security positions," the senators wrote.

As the letter was released, one Justice Department memo surfaced in news reports describing the administration's drone-attack authority.

As first reported Monday night by NBC News, the memo says it is legal for the government to kill U.S. citizens abroad if it believes they are senior Al Qaeda leaders continually engaged in operations aimed at killing Americans -- even if there is no intelligence pointing to an active plot against America.

The 16-page document says that delaying action against individuals continually planning to kill Americans would create an unacceptably high risk. It adds that the threat posed by Al Qaeda and its associated forces demands a broader concept of when a person continually planning terror attacks presents an imminent threat.

It's unclear whether that will satisfy lawmakers' concerns.

Under Obama, the U.S. drone program has ramped up dramatically. It has become one of the most important tools in the administration's counterterrorism campaign -- particularly in Pakistan, but also in the expanding fronts of the war against Al Qaeda and its affiliates. The senators' questions follow a 2011 drone strike in Yemen that killed two Americans -- Anwar al-Awlaki and Samir Khan.

While Awlaki was considered a powerful terror operative for Al Qaeda in the Arabian Peninsula, he was never charged. In their letter Monday, the senators said they believe there are "circumstances" where a U.S. president can use "lethal force" against Americans who "choose to take up arms" against their country, "just as President Lincoln had the authority to direct Union troops to fire upon Confederate forces during the Civil War."

But they said "it is vitally important" for Congress and the public to understand how the administration interprets the limits on that power. They complained that the administration has ignored prior requests for legal opinions from the Justice Department.

Brennan, a vocal supporter of the drone program and other controversial counterterrorism tools dating back to the George W. Bush administration, is facing a level of criticism from Democrats that no other Obama nominee has encountered. Eight Democrats and three Republicans penned the letter to Obama Monday. One of them, Sen. Ron Wyden, D-Ore., has previously pressed Brennan on the drone issue.

Another, Sen. Mark Udall, D-Colo., said last week he was "deeply disappointed" coming out of a meeting with Brennan. He claimed the White House counterterrorism adviser was "unprepared" to discuss a recent report on the CIA detention and interrogation program.

READ FULL SOURCE ARTICLE: 02/05/2013