At the end of a mostly civil hearing Tuesday in which former federal officials advised senators against limiting President Donald Trump’s authority to launch nuclear weapons, Trump critic Sen. Bob Corker (R-Tenn.) emphasized the importance of ongoing nuclear deterrent modernization programs.

“Many of us have been to the facilities where [nuclear weapons] are modernized [and] it’s amazing that some of the guidance systems in [the weapons] are not much more sophisticated that the tubes on a black and white television,” Corker said at the conclusion of a two-hour hearing of the Senate Foreign Relations Committee. “We need to continue to invest…in the proper technologies.”CAPITOL

Two of the three witnesses at the hearing agreed.

“People who are worried about nuclear war should be in favor of reasonable modernization,” said Peter Feaver, a professor of political science and public policy at Duke University in Durham, N.C. Feaver was director for defense policy and arms control on the National Security Council in the Clinton administration.

Brian McKeon, former acting undersecretary for policy at the Pentagon in the Barack Obama administration, likewise said he favors “recapitalization for both the warheads and the triad.”

In a late October report, the Congressional Budget Office said it would cost $1.2 trillion over 30 years to maintain and update the U.S. nuclear deterrent. That would include $261 million at the Department of Energy.

Corker, whose home state hosts DoE’s Y-12 National Security Complex that refurbishes the uranium-based secondary stages of nuclear warheads, declared earlier this year he would not seek re-election in 2018. The Foreign Relations Committee chairman has since become an increasingly vocal critic of Trump.

The Atomic Energy Act of 1946 gives the president of the United States sole authority to authorize a nuclear strike.

The witnesses urged the committee not to tie the president’s hands when it comes to retaliatory nuclear strikes, and retired U.S. Strategic Command chief Air Force Gen. C. Robert Kehler said existing safeguards are enough to prevent Trump or any other president from initiating an illegal, unilateral first strike.

Republicans and Democrats mostly agreed that Trump should be empowered to deploy nuclear weapons if his military and intelligence advisers are convinced an unfriendly nation has launched, or might very soon launch, a nuclear strike against the United States.

But for some Democratic senators, the elephant in the room was whether Congress should bar Trump and his successors from ordering a wartime first strike.

“We are concerned that the president is so unstable and volatile and has a decision-making process that is so quixotic that he might order a nuclear strike that is out of step with U.S. national security interests,” Sen. Chris Murphy (D-Conn.) said about an hour into the proceedings.

One of Murphy’s colleagues put it more colorfully:

“The president’s bombastic words could turn into nuclear reality,” Sen. Ed Markey (D-Mass.) said. Markey is the author of a Senate bill that would prohibit the president from unilaterally launching a nuclear first strike.

Markey’s bill, or anything like it, was a bridge too far for the witnesses, none of whom thought Congress should legislatively dilute the president’s existing authority.

Meanwhile, Rep. Adam Smith (D-Wash.) on Wednesday introduced exceptionally short legislation that would prevent the United States from initiating a nuclear first strike against a foe.

The bill has just one section, which reads in total: “Section 1. Policy on No-First-Use of Nuclear Weapons. It is the policy of the United States to not use nuclear weapons first.”

“The United States should not use nuclear arms in a first strike,” Smith, ranking Democrat on the House Armed Services Committee, said in a prepared statement. “They are instruments of deterrence, and they should be treated as such. A declaratory policy of not using nuclear weapons first will increase strategic stability, particularly in a crisis, reducing the risk of miscalculation that could lead to an unintended all-out nuclear war.”

Near the end of his term, former President Barack Obama reportedly considered changing U.S. policy that allows for nuclear first strikes, but never followed through. Reports in late 2016 indicated there was opposition to such a move from top members of Obama’s Cabinet and U.S. allies including Japan and the United Kingdom.

Legislation filed in both chambers earlier this year by Markey and Rep. Ted Lieu (D-Calif.) would require congressional authorization for a nuclear first strike.

It was not immediately clear Wednesday afternoon how many lawmakers had signed onto Smith’s bill, or to which committee it was directed. Nonetheless, it was quickly lauded by a number of nonproliferation organizations.

“@RepAdamSmith introduced a #NoFirstUse bill today, elegant in its simplicity and intelligence,” the Ploughshares Fund said on Twitter.