President Barack Obama spoke about the “future of terrorism,” in his president’s speech at the National Defense University on Thursday.

Obama initially focused on the threat that faces the United States.

“America is at cross-roads, we must define the nature and scope of this struggle....Neither I, nor any president can promise the total defeat of terror,” he added.

The president stated that the U.S.’s fight against terrorism was justified in so far as it constituted self-defense.

“We are at war with an organization that right now would kill as many Americans as they could if we did not stop them first. So this is a just war – a war waged proportionally, in last resort, and in self-defense.”

What we must do, he stated, is dismantle networks that pose a direct danger.

He went on to address the growth of, what he termed, an extremist presence in the Middle East.

“Unrest in the Arab world has allowed extremism to gain a foothold in…Libya and Syria.

“In some cases we confront state-sponsored networks like Hezbollah,” he added, in reference to the Lebanese group which is currently the focus of a British attempt to place its armed force on the European Union’s terror list.

This fight against terrorism, Obama said, must involve addressing the underlying grievances and conflicts that feed extremism.

“This means patiently supporting transitions to democracy in places like Egypt, Tunisia and Libya. We must strengthen the opposition in Syria,” he added.

The deteriorating political and security conditions in some countries in the region has led to their being a soft target.

“Al-Qaeda, and its affiliates, try to gain a foothold,” in such countries as Somalia and Yemen, whose political situations have led to worsening security situations therein, he stated.

The solution is foreign aid, announced Obama, despite it being the least popular government expenditure, according to the president.

“Foreign assistance is fundamental to [American] national security,” it should not be seen as charity.

Obama’s speech paid special attention to the case of drone strikes, which the U.S. operates in Yemen and Pakistan. He defended his administration’s use of drones to kill terrorists abroad, and in a nod to concerns, outlined plans to limit the use of such strikes.

“Lethal force may only be used to prevent or stop attacks against U.S. persons, never as a form of punishment or in lieu of prosecution… There must be a legal basis for using lethal force,” he added.

He then went on to voice his own concerns; the “precision” and “secrecy” of drone strikes “can lead a president to and his team to view [them] as a cure-all for terrorism.”

It is for this reason, stated Obama, that transparency and debate on the issue must be facilitated.

The president reaffirmed his disregard for Guantanamo prison, which was set up by his predecessor, George W. Bush. The original premise for opening the prison, he stated, was so that detainees would not be able to challenge their detention.

“This was found unconstitutional five years ago.”

He went on to state there is no justification, beyond politics, for the American Congress to prevent the closure of the facility. Obama has long argued for prosecuting enemy combatants in civilian courts and transferring those cleared of wrongdoing to their home countries.

Home-grown terror threats were also addressed in the speech on the U.S.’s national security, Obama discussed the balance between ensuring security and promoting civil liberties and stated that the country’s commitment to civil freedoms made “thwarting home-grown [terrorism]…a particular challenge.”

In light of this, he reaffirmed his commitment to the process of a fair trial and the protection of sensitive information by the government.

“America, we have faced greater challenges than al-Qaeda,” he stated, “now, we need a strategy-and a politics- that reflects this resilient spirit.”

An anti-war heckler repeatedly interrupted President Barack Obama during the speech, prompting him to depart from his prepared remarks.

“The voice of that woman is worth paying attention to - obviously I don’t agree with much of what she said,” Obama said, after repeatedly asking the woman to sit down.

“She wasn’t listening to me, in what I said - but these are tough issues and the suggestion that we can gloss over them is wrong,” Obama said