Congress questions commander-in-chief’s sole nuclear authority

Judy Woodruff:

On the other side of the Capitol, Senators focused on President Trump's power to launch a nuclear war.

Nick Schifrin reports on this critical chain of command.

Nick Schifrin:

In a world full of threats, Senate Democrats today asked whether the biggest threat is in the White House.

Sen. Edward Markey:

Donald Trump can launch nuclear codes just as easily as he can use his Twitter account.

Nick Schifrin:

The United States' nuclear command structure was born out of the Cold War.

Narrator:

The Soviets continue to develop and deploy strategic offensive nuclear forces.

Nick Schifrin:

Pentagon videos described the Soviet threat as imminent. The president needed to be able to launch nuclear weapons quickly, in case the U.S. was being attacked.

Tennessee Republican Bob Corker-

Sen. Bob Corker:

This process means the president has the sole authority to give that order.

Nick Schifrin:

Today, the threat comes North Korean intercontinental ballistic missiles. U.S. intelligence predicts they could soon carry a nuclear warhead. President Trump has threatened preventive war.

President Donald Trump:

They will be met with fire and fury, like the world has never seen. Rocket Man is on a suicide mission for himself and for his regime.

Sen. Edward Markey:

Many Americans share my fear that the president's bombastic words could turn into nuclear reality.

Nick Schifrin:

The president has the sole authority to launch nuclear weapons. But that doesn't mean he can launch a weapon for no reason, whenever he wants, said Duke Professor Peter Feaver, who studied nuclear command for 30 years.

Peter Feaver:

Where the military wakes up the president and warns him that there is about to be an attack, or that we're experiencing an attack, he alone would have the authority to make the decision.

But in the other context, where the president is waking up the military, maybe in an extreme funk, saying, I'm angry and I want something done, in that setting, he requires the cooperation of a lot of people.

Nick Schifrin:

That cooperation wouldn't be forthcoming if his order were illegal, said retired General Robert Kehler, the former head of U.S. Strategic Command.

Gen. Robert Kehler:

The United States military doesn't blindly follow orders. A presidential order to employ U.S. nuclear weapons must be legal. The basic legal principles of military necessity, distinction, and proportionality apply to nuclear weapons, just as they do to every other weapon.

Nick Schifrin:

Maryland Democrat Ben Cardin-

Sen. Ben Cardin:

Do you believe that under — because of legalities, you retain that decision to disobey the commander in chief?

Gen. Robert Kehler:

Yes. If there is an illegal order presented to the military, the military is obligated to refuse to follow it.

Nick Schifrin:

Today's hearing was called by Senate Republicans, but many of them urged extreme caution. They said the U.S.' adversaries needed to understand the president is still the sole person able, and is still willing, to use nuclear weapons.

Sen. Marco Rubio:

We cannot have a bunch of bunker lawyers that basically — or activists, up and down the chain, who decide that they're going to disobey any order that they disagree with.

Sen. James Risch:

Pyongyang needs to understand that they are dealing with a person who is commander in chief right now who is very focused on defending this country, and he will do what is necessary to defend this country.

Nick Schifrin:

Democrats have introduced legislation that would limit the president's nuclear authority. Some today questioned whether sound legal advice would prevail in a nuclear weapons discussion.

Massachusetts Democrat Ed Markey questioned whether presidential advisers, current and former generals, could constrain the president.

Sen. Edward Markey:

I don't think we should be relying upon a group of individuals to be resisting an illegal order, when they have all pretty much been hired by the president.

Nick Schifrin:

Since President Harry Truman became the only person ever to have ordered a nuclear strike, U.S. law said only a president should carry the nuclear responsibility.

But, today, that singular authority is being questioned.

For the PBS NewsHour, I'm Nick Schifrin.