Attorney General Eric Holder can imagine a scenario in which it would be constitutional to carry out a drone strike against an American on American soil, he wrote in a letter to Sen. Rand Paul, R-Ky.

“It is possible, I suppose, to imagine an extraordinary circumstance in which it would be necessary and appropriate under the Constitution and applicable laws of the United States for the President to authorize the military to use lethal force within the territory of the United States,” Holder replied in a letter yesterday to Paul’s question about whether Obama “has the power to authorize lethal force, such as a drone strike, against a U.S. citizen on U.S. soil, and without trial.”

Paul condemned the idea. “The U.S. Attorney General’s refusal to rule out the possibility of drone strikes on American citizens and on American soil is more than frightening – it is an affront the Constitutional due process rights of all Americans,” he said in a statement.

Holder noted that Paul’s question was “entirely hypothetical [and] unlikely to occur,” but cited the September 11, 2001 terrorist attacks as the type of incidents that might provoke such a response.

“Were such an emergency to arise, I would examine the particular facts and circumstances before advising the President on the scope of his authority,” he concluded.

Sen. Mike Lee, R-Utah, an attorney and Judiciary Committee member, told The Washington Examiner last month that the drone policy so far outlined by the administration is too vague.

“That has the potential to swallow the rule,” Lee said after the drone program white paper was leaked. “If you’re going to regard somebody as presenting an imminent threat of an attack on the U.S. simply because you have concluded that they are an ‘operational leader’ or they are involved in planning an attack in one way or another, you find yourself giving way to much discretion to the government.”

Lee said that the White House should release the formal legal analysis underpinning the drone program. “We know that in some instances where the government has released its legal analysis, it gets it wrong,” he said.