For the United States and NATO members, that could mean reemphasis on an aspect of NATO’s Cold War defense policy.  In the 1960s, 1970s and early 1980s, NATO allies faced Soviet and Warsaw Pact conventional forces that had large numerical advantages, and NATO leaders had doubts about their ability to defeat a Soviet/Warsaw Pact attack at the conventional level. NATO policy thus explicitly envisaged that, if direct defense with conventional means failed, the Alliance could deliberately escalate to nuclear weapons. That left many senior NATO political and military officials uneasy. Among other things, it raised uncomfortable questions about the willingness of an American president to risk Chicago for Bonn.

Russia found itself in a similar situation at the end of the 1990s. With a collapsing economy following the break-up of the Soviet Union, the Russian government had to cut defense spending dramatically. As its conventional capabilities atrophied, Moscow adopted a doctrine envisaging first use of nuclear weapons to compensate. (In the past fifteen years, as Russia’s defense spending has increased, a significant amount has gone to modernizing conventional forces.)

The United States and NATO still retain the option of first use of nuclear weapons. If the U.S. president and NATO leaders were to consider resorting to that option, they then would be the ones to have to consider the dicey bet that the other side would not respond with nuclear arms or that, if it did, nuclear escalation somehow could be controlled.

Assuring NATO allies that the United States was prepared to risk Chicago for Bonn consumed a huge amount of time and fair amount of resources during the Cold War. At one point, the U.S. military deployed more than 7000 nuclear weapons in Europe to back up that assurance. Had NATO had sufficiently strong conventional forces, the Alliance would have been able to push that risky decision regarding nuclear first use onto Moscow—or even have been able to take comfort that the allies’ conventional power would suffice to deter a Soviet/Warsaw Pact attack.

In modernizing, maintaining and operating a safe, secure and effective nuclear deterrent, the United States should avoid underfunding conventional forces in ways that increase the prospect of conventional defeat and/or that might tempt an adversary to launch a conventional attack. If Washington gets the balance wildly out of sync, it increases the possibility that the president might face the decision of whether to use nuclear weapons first—knowing that first use would open a Pandora’s box of incalculable and potentially catastrophic consequences.

Getting the Balance Right in the COVID19 Era

This means that the Department of Defense and Congress should take a hard look at the balance. The Pentagon presumably has weighed the trade-offs, though it is not a unitary actor.  “Nuclear weapons are our top priority” has been the view of the leadership. The trade-offs have been easier to manage in the past several years, when nuclear programs were in the research and development phase, and defense budgets in the first three years of the Trump administration grew. As nuclear programs move into the more expensive procurement phase and the fiscal year 2021 budget shows little increase, the challenge of getting the balance right between nuclear and conventional spending has become more acute. It is not apparent that the Pentagon has weighed the opportunity costs over the next ten-fifteen years under less optimistic budget scenarios.

As for Congress, which ultimately sets and approves the budget, no evidence suggests that the legislative branch has closely considered the nuclear vs. conventional trade-offs.

All that was before COVID19. The response to the virus and dealing with the economic disruption it has caused have generated a multi-trillion-dollar budget deficit in 2020 and likely will push up deficits in at least 2021. It would be wise now to consider the impact of COVID19.

Having added trillions of dollars to the federal deficit, and facing an array of pressing health and social needs, will Congress be prepared to continue to devote some 50 percent of discretionary funding to the Department of Defense’s requirements? Quite possibly not. If defense budgets get cut, the Pentagon will face a choice:  shift funds from nuclear to conventional force programs, or accept shrinkage of U.S. conventional force capabilities and—as the United States did in the 1950s and early 1960s—rely on nuclear deterrence to address a broader range of contingencies. In the latter case, that would mean accepting, at least implicitly, a greater prospect that the president would have to face the question of first use of nuclear weapons, i.e., a conventional conflict in which the United States was losing.

This is not to suggest that the U.S. military should forgo the strategic triad. Trident II SLBMs onboard ballistic missile submarines at sea remain the most survivable leg of the strategic deterrent. The bomber/air-breathing leg offers flexibility and can carry out conventional missions. The ICBM leg provides a hedge against a breakthrough in anti-submarine warfare. Moreover, if in a crisis or a conventional conflict, the Russian military were to develop the capability to attack U.S. ballistic missile submarines at sea, the Kremlin leadership might well calculate that it could do so without risking a nuclear response. Attacking U.S. ICBMs, on the other hand, would necessitate pouring hundreds of nuclear warheads into the center of America. A Russian leader presumably would not be so foolish as to think there would be no nuclear retaliation.

While sustaining the ICBM leg, one can question whether maintaining 400 deployed ICBMs, as the current plan envisages, is necessary. Reducing that number for the Ground-Based Strategic Deterrent (GBSD) would achieve budget savings, albeit later in the production run.  Another question is whether some way might be found to extend the service life of some portion of the current Minuteman III force that would allow delaying the GBSD program, which is projected to cost $100 billion, by ten-fifteen years and postponing those costs—freeing up funds in the near term for conventional force requirements.

Another issue concerns the Long-Range Standoff Missile (LRSO) and its cost, estimated at some $20 billion when including the nuclear warheads. The B-21 bomber will incorporate stealth and advanced electronic warfare capabilities allowing it to operate against and penetrate sophisticated air defenses. The LRSO, to be deployed beginning in 2030, is intended to replace older air-launched cruise missiles carried by the B-52 bomber and could later equip the B-21 if it loses its ability to penetrate.

An alternative plan would convert B-52s in 2030 to conventional-only missions and delay the LRSO to a future point if/when it appeared that the B-21’s ability to penetrate could come into question. By 2030, the Air Force should have a significant number of B-21s (the B-21 is scheduled to make its first flight in 2021 and enter service in 2025). With at least 100 planned, the Air Force should have a sufficient number of B-21s for the 300 nuclear weapons it appears to maintain at airfields where nuclear-capable bombers are currently based.

These kinds of ideas would free up billions of dollars in the 2020s that could be reallocated to conventional weapons systems. Delaying the GBSD and LRSO and their associated warhead programs by just one year (fiscal year 2021) would make available some $3 billion—enough money for a Virginia-class attack submarine.  Delaying those programs for ten-fifteen years would make tens of billions of dollars available for the military’s conventional force needs.

All things being equal, it is smarter and more efficient to choose to make decisions to curtail or delay major programs rather than to continue them until the money runs out and forces program termination. As it examines the administration’s proposed fiscal year 2021 defense budget, Congress should carefully consider the trade-offs and press the Pentagon to articulate how it weighed the trade-offs between nuclear and conventional forces. In the end, Congress should understand whether it is funding the force that is most likely to deter not just a nuclear attack, but to deter a conventional conflict that could entail the most likely path to nuclear war.

Steven Pifer is a William Perry Research Fellow at Stanford’s Center for International Security and Cooperation and retired Foreign Service officer.