There has been a lot of talk about how the Biden administration might focus on America’s alliances when approaching foreign policy. But missing in this conversation is any discussion of reinforcing our commitments to extended deterrence. As Commander of Air Force Global Strike Command Gen. Timothy Ray recently reminded us, U.S. extended deterrence “is an important part of [our allies’] strategic calculus.”

Since the end of World War II, the United States has committed its nuclear forces to deter not only attacks against the United States, but also attacks against U.S. allies. If the incoming Democratic administration wants to strengthen alliances, it must focus on assuring our allies this commitment remains inviolate.

The U.S. nuclear umbrella covers thirty non-nuclear states, an arrangement that the United States has historically preferred as part of its commitment to nuclear nonproliferation. Without this promise of extended deterrence, more nations might push to acquire their own nuclear weapons. Such an outcome can worsen crisis instability and increase the odds of strategic miscalculation.

America’s allies and partners also benefit from U.S. extended deterrence. For example, the United States deployed tactical nuclear weapons in Europe during the Cold War to deter Russia from conventionally attacking European allies. South Korea relies on the U.S. nuclear triad to deter a nuclear attack by its belligerent neighbor to the north.

Extended deterrence gains importance as the nuclear threat to our allies increases. Russia possesses an unconstrained and growing stockpile of tactical nuclear weapons and has fielded new theater-range delivery systems like an air-launched ballistic missile. Its apparent “escalate to win” nuclear doctrine indicates a greater willingness to use these nuclear weapons on the battlefields in Europe.

China is expected to double the size of its nuclear stockpile over the next decade and continues to field a variety of missiles capable of striking targets in the Indo-Pacific region. And then there’s North Korea, developing capabilities like sea-launched ballistic missiles that can launch nuclear weapons in the region with a better chance at avoiding missile defenses.

After the election, Biden phoned our allies in the Pacific to begin, as he called it, “repairing frayed partnerships” and reassure the U.S. commitment to help defend against such threats. In particular, he expressed to Japanese prime minister Suga his “deep commitment to the defense of Japan.”

The issue, though, is that despite the Biden administration’s pledge to “renew America’s alliances,” some proposals bubbling inside the Democratic platform would hinder—not improve—U.S. security commitments toward its allies.

Significantly, leaders on the left are pushing for a Biden administration to cut funding for U.S. nuclear modernization programs that are critical to ensuring a credible extended deterrent.

Most of the systems that comprise our nuclear triad—our long-range missiles, bombers, and nuclear submarines—are decades-old, and set to retire nearly a half a century beyond their intended lifetimes.

For example, the air-launched cruise missile carried by bombers was designed in 1974 but now expected to last through 2030. This capability especially contributes to the credibility of U.S. extended deterrence by enabling the United States to deploy bombers in theater to literally show an adversary its willingness to defend its allies.

Some critics have proposed canceling the air-launched cruise missile’s modern replacement, the Long-Range Standoff Weapon (LRSO). This flies in the face of statements by experts such as Lt. Gen. (ret.) Jack Weinstein, who led nuclear deterrence efforts for the Air Force and said that “NATO and our allies are extremely supportive of our LRSO project.”

House Armed Services Committee Chairman Rep. Adam Smith and others have also proposed the United States adopt a dangerous nuclear declaratory policy of “No First Use.” This means that the United States would pledge not to use nuclear weapons first against its adversaries during conflict—an idea to which its allies object.

For deterrence to be effective, it must be credible in the mind of U.S. adversaries, meaning that they must be convinced that the United States is both capable and willing to use nuclear weapons. It’s certainly a paradox. As former Commander of U.S. Strategic Command, General Robert Kehler has explained, “to prevent the use of nuclear weapons, the U.S. must remain prepared to use them.”

A No First Use policy signals to America’s allies that it may be unwilling to come to their aid no matter the circumstances, including chemical, biological, or overwhelming conventional attacks. Pledging to not use nuclear weapons first only reassures America’s adversaries, not its allies.

Ultimately, if Joe Biden wants to value alliances as a pillar of U.S. strength, then he needs to prioritize extended deterrence. That means fully resourcing the nuclear modernization programs that assure our allies and avoiding bad ideas like implementing a No First Use policy.

Strengthening relationships with allies is a worthy goal. To fully demonstrate that commitment to our allies, the next administration must prioritize extended deterrence.