David Welna

Secretary of State Rex Tillerson has raised the prospect of pre-emptive action as a way the U.S. and its allies could deal with the threat of North Korea's nuclear missiles. NPR takes a look at the state of the North's nuclear and missile programs, and what kind of conventional threat it also poses to its neighbors.

Investigations into Russian election meddling and Trump's claims of being wiretapped are getting underway in Congress. But Democrats and Republicans aren't on the same page.

President Trump has reportedly reversed an Obama-era policy of giving more responsibility for terrorist drone strikes to the Pentagon. The CIA will resume more responsibility for not only generating intelligence but also conducting strikes — and reaction in the national security world is mixed.

A U.S. general says Russia has violated a longstanding arms control treaty by deploying new missiles. It was the first official, public assertion that these missiles are fully operational.

After weeks of reports that Russia is violating a nuclear arms treaty with the U.S., the Pentagon says that is indeed the case. Top nuclear arms officials are telling Congress that Moscow is deploying prohibited intermediate range nuclear weapons that could be used to attack Europe. It's another nuclear headache for a new administration also grappling with defiant nuclear weapons moves by North Korea.

On Capitol Hill, news about the attorney general came as the House Intelligence Committee agreed on the scope of its investigation into Russia's meddling in the 2016 presidential election.

Committees in Congress are gearing up to conduct their investigations into the role Russia played during the 2016 presidential campaign — and the ties it may have had to the man who won it.

President Trump ridiculed his predecessor and Hillary Clinton for refusing to use the term "radical Islamic terrorism." Turns out his new national security adviser, Gen. H.R. McMaster, is also opposed to using the phrase since he finds the groups the U.S. is fighting in the Middle East not Islamic. But that has not stopped Trump from repeating it, to the delight of his base.

Sebastian Gorka responded to critical posts on Twitter by threatening to involve White House lawyers. He is fighting questions about his credentials and his views on Islam.

Sebastian Gorka is British-born, Hungarian-educated, and a self-described expert on Islamists — who doesn't speak Arabic. As Trump's deputy assistant, he has his boss' ear and security experts' ire.

Japanese Prime Minister Shinzo Abe meets with President Trump Friday. Their two countries have a long military alliance. But the presence of U.S. troops on the Japanese island of Okinawa is controversial.

President Trump inherited 41 "law of war" captives in Guantanamo, well below the 242 there when Barack Obama took office. A visit to the prison camps finds them ready for more occupants.

The military commissions for terrorism suspects at Guantanamo Bay have resumed. Former President Obama failed to close the prison. But President Trump has vowed to keep it open and send new detainees.

American B-2 stealth bombers destroyed a nest of ISIS military camps in Libya late Wednesday, the Pentagon said. It's the latest in a long series of American airstrikes designed to set back the progress of the terror group's efforts to spread from its home base in Iraq and Syria. Libya has been in chaos since U.S. and European militaries helped depose its onetime ruler without replacing him with a viable new government.

President Obama is the first president to serve eight years with the U.S. at war nonstop, from beginning to end. Donald Trump now inherits ongoing conflicts in Syria, Iraq and Afghanistan.

President-elect Trump will inherit ongoing conflicts with no end in sight when he takes the oath of office — a brutal fight against the Islamic State and a never-ending stalemate in Afghanistan.

Kansas Rep. Mike Pompeo is scheduled to appear before the Senate Intelligence Committee on Thursday for his confirmation hearing to become President-elect Trump's director of the CIA. Pompeo is expected to face questioning about the role Russia played in meddling in the U.S. presidential election, the war against ISIS and other challenges. He is expected to be confirmed.

In the debate over Russian hacking, WikiLeaks founder Julian Assange has been praised by President-elect Donald Trump despite his controversial past.

In the battle to retake Mosul from ISIS, the Qayyarah Airfield West is a key staging base run by Iraqi and U.S. forces. Ash Carter visited there Dec. 11 and awarded medals to eight Iraqi soldiers.

Defense Secretary Ash Carter visited Baghdad on Sunday to discuss the battle to retake Mosul from ISIS. On Monday, he's in Israel, which becomes the first U.S. ally to receive the F-35 fighter.