WASHINGTON (CNN) -- From the targeted killing of Americans overseas to the future of the military prison at Guantanamo Bay, President Barack Obama will lay out the framework and legal rationale for his administration's counterterrorism policy in a widely anticipated speech Thursday.

Administration officials tell CNN that Obama will use the National Defense University speech to continue to call on engagement with Congress on aspects of national security, more transparency in the use of drones, and a review of threats facing the United States.

He will make the case that the al Qaeda terror network has been weakened, but that new dangers have emerged even as the U.S. winds down operations in Afghanistan after more than a decade of war triggered by the 9/11 attacks.

Threats that have emerged come from al Qaeda affiliates, localized extremist groups, and homegrown terrorists.

The address will also build on remarks Obama made in his annual State of the Union address earlier this year when he said his administration works "tirelessly to forge a durable legal and policy framework to guide our counterterrorism efforts."

It also comes on the heels of a couple confirmation hearings on Capitol Hill for members of Obama's national security team where a pitched political battle over the use of drones was waged.

At John Brennan's confirmation hearing to be CIA director, Republican Sen. Rand Paul of Kentucky mounted a 13-hour filibuster demanding the administration detail whether it would be legal to strike suspected American terrorists on U.S. soil.

Attorney General Eric Holder responded in a letter to Paul that the president did not have such authority.

In a letter to congressional leaders on Wednesday, Holder disclosed the administration had deliberately killed Anwar al-Awlaki, an American citizen and radical Muslim cleric who was said to be the face of the al Qaeda franchise operating in Yemen.

Holder said he was actively plotting to attack the United States and so targeting him was justified legally and from a policy standpoint.

"This disclosure was also intended to coincide with the speech the president will give (Thursday) in which he will discuss our broader counter-terrorism strategy - including the policy and legal rationale for our use of targeted, lethal force against al Qaeda and its associated forces," a White House official told CNN.

The letter also disclosed that three other Americans were killed overseas in counterterror strikes but that those suspected terror figures were not deliberately targeted by the United States.

In an interview with CNN Chief White House Correspondent Jessica Yellin last year, Obama said the drone issue was a daily "struggle" for him.

"That's something that you have to struggle with," he said. "Because if you don't, it's very easy to slip into a situation in which, you end up bending rules, thinking that the ends always justify the means. That's not been our tradition. That's not who we are as a country."

The administration is considering shifting lethal drone operations currently run by the CIA over to the military "due to a desire for greater transparency in who is being targeted," a U.S. official told CNN earlier this week.

By law, the military is not able to act in the covert way the CIA can in this particular arena, and must answer to Congress.

In his confirmation hearing, Brennan expressed a desire to move the agency away from paramilitary operations, and back to traditional areas of espionage.

"The CIA should not be doing traditional military activities and operations," he said.

The American public is split on where and how drones should be used, according to a March poll by Gallup.

Although 65% of respondents said drones should be used against suspected terrorists abroad, only 41% said drones should be used against American citizens who are suspected terrorists in foreign countries.

This number dips even further when the use of drones on American soil is considered. Only 25% of people said drone should be used against suspected terrorists in the United States. And when that suspected terrorist is an American citizen, the approval for using drones falls to 13%.

Another flashpoint Obama will discuss is the fate of the Guantanamo Bay, Cuba, detention facility.

While he worked to close it early in his first term, Congress enacted significant restrictions on the transfer of detainees from the prison that made its closure impractical.

Earlier this year, the State Department reassigned the special envoy who had been assigned in 2009 to deal with closing the facility and lowered the post's profile by assigning the job to the department's legal adviser's office.

"Guantanamo hasn't been a full time job for a year," one senior administration official told CNN earlier this year in reference to the congressional restrictions on the repatriation of detainees who have been cleared for release.

But with more than half the facility's 166 inmates engaging in various forms of hunger strike, more than 20 of them being force fed, the failure to close the facility established in 2001 is a continuing problem for the administration.

There are some 86 inmates at Guantanamo that have been cleared for transfer, 56 of them from Yemen.

At Wednesday's briefing, Press Secretary Jay Carney said Obama is "considering a range of options" to reduce the prison's population.

"I would say that one of the options is reappointing a senior official at the State Department to renew our focus on repatriating or transferring those detainees," Carney said.

The Wall Street Journal reported on Thursday the Obama administration was ready in the coming weeks to jump start efforts to close the prison - including lifting the prohibition on sending detainees to Yemen.

"We're in the process of working on that now, we're looking at candidates," who could lead the process of helping close Guantanamo, Attorney General Eric Holder said at a press conference earlier this month. "The president has indicated that it's too expensive, that it's a recruitment tool for terrorists, it has a negative impact on our relationship with our allies, and so we're going to make a renewed effort to close Guantanamo."

Most Americans still support keeping the prison open at Guantanamo Bay.

Seventy percent of respondents to a February 2012 ABC/Washington Post poll said they approve of keeping the facility open for suspected terrorists. Only 24% said it should be closed.

CNN's Elise Labott, Chris Lawrence, Barbara Starr and Dan Merica contributed to this report.