Where will the next president stand on nuclear weapons?

From Hiroshima to the Cuban Missile Crisis, from arms races to arms control, from the Cold War and its proxy wars to the 2003 invasion of Iraq and the 2015 deal with Iran, few subjects have so consistently, and so controversially, concerned the American presidency as nuclear weapons have. A dozen men have been responsible for the decision to use the US nuclear arsenal since 1945, and whoever wins the election in November will inherit the responsibility for approximately 4,670 warheads at a time when relations with Russia (holder of 4,500 warheads) have reached a perilous low, a time when support for arms control is perhaps faltering, and a time when nuclear threats abound from the Middle East to the Korean Peninsula. Attempting to predict precisely how a candidate will govern after Election Day is always challenging. Presidential hopefuls often rely on rhetoric to get elected, and once in office confront numerous complex factors that crowd the decision-making environment and impact eventual policy choices. Still, issues like nuclear war and nuclear proliferation are too important to ignore until a new commander in chief assumes office next January. And although the topic has hardly gotten the attention it deserves in the election so far, most of the leading candidates have said enough about nuclear weapons that we can examine their positions in some detail. In fact, as ongoing academic research suggests, a candidate’s prior views on nuclear weapons may be more likely to influence his or her eventual policy choices as president.

The dealmaker. The most surprising thing about the candidates’ positions on nuclear policy might be that Donald Trump, the one contender who has never held public office, boasts a plentiful record on the topic, extending back at least as far as a 1987 interview with journalist Ron Rosenbaum. The author of a 2011 book about nuclear war, Rosenbaum recently recounted the episode for Slate, who also republished his original article, all of which makes for interesting reading. Rosenbaum recalls that Trump “seemed genuinely aware of just how much danger nukes put the world in” and how little had been done about it. The real-estate mogul, then in his early 40s, questioned the wisdom of popular nuclear-deterrence policies and said his uncle, a scientist at MIT, had gotten him interested in nuclear proliferation and terrorism. As he still does today, Trump identified proliferation as the number one problem confronting the United States—a position that’s difficult to reconcile with his recent comments supporting selective proliferation to key American allies. Still, it’s clear that Trump has engaged the issue of nuclear weapons since the days of the Reagan administration, and, if Rosenbaum’s original assessment still applies, has done so sincerely.

In 1987, with the Cold War still at the forefront of nuclear discussions, Trump pushed for Washington to do more with Moscow on the nuclear portfolio. Yet he seemed just as worried about potential failures of deterrence outside the US-Soviet relationship—between India and Pakistan, for example (Pakistan would ultimately acquire nuclear weapons in 1998), or as a bulwark against a terrorism-sponsoring dictator like Libya’s Muammar Qaddafi, with whom he had a particular fascination. He also worried about “countries like France … blatantly selling nuclear technology.” His solution, not surprisingly given his profession, was a deal—a deal with the Soviet Union to prevent other states from going nuclear at all costs. It involved the Americans and the Soviets using economic pressure in their respective spheres of influence to forestall proliferation. When pressed, Trump reluctantly advocated using military force if economic punishments failed. “It’s not that [I] think he’s got the solution,” Rosenbaum wrote at the time, “but I like the visionary urgency he brings to the problem.”

Thirteen years later, Trump would advocate a similar position, with less reluctance, while discussing North Korea in his 2000 campaign book The America We Deserve: “Am I ready to bomb this reactor? You’re damned right. When the Israelis bombed the Iraqi nuclear reactor they were condemned … But they did what they had to do to survive.” In that same book he praised Richard Nixon (he of the “madman” school of foreign relations) for his work in bringing the Russians to the table for the first serious arms-control negotiations between the two superpowers and lauded Ronald Reagan for being “crazy like a fox,” a quality the Nobel laureate Thomas Schelling touted in his 1966 book Arms and Influence: “Another paradox of deterrence is that it does not always help to be, or to be believed to be, fully rational, cool-headed, and in control of oneself or one’s country.” Whether in the nuclear context or in describing US intervention policy, one can’t help but get the sense that Trump believes American leaders talk too much, telling our adversaries just what we’ll do and when.

In his 2011 book Time to Get Tough, Trump expanded his views on counter-proliferation and extended deterrence. He pointed to Israel, for whom keeping all options on the table—including military force—has proven effective against previous proliferation challenges. Foreshadowing his most recent comments about allied free-riding, he also described how South Korea “likes our military defending them against North Korea.” Recently, this last point brought Trump significant criticism for his seeming renunciation of decades of American policy—advocating that South Korea, Japan, and Saudi Arabia might benefit from going nuclear instead of using the American nuclear umbrella for protection.

Trump was similarly criticized by opponent Ted Cruz for not knowing what the nuclear triad was, and for not having an answer about which leg(s) should be prioritized under proposed modernization plans. (Cruz stated his support for the modernization plans and said the submarine leg of the triad was its most significant priority.) Trump’s most recent comments, in a speech in Washington last week dedicated to his foreign policy, are critical of the Obama administration for allowing the nuclear arsenal to “atrophy,” but are ambiguous about his potential support for the current modernization proposal. Trump and Cruz do agree, however, on the use of tactical nuclear weapons against ISIS—a remarkably explicit position for candidates or leaders to utter. (As Cruz said, “I don’t know if sand can glow in the dark, but we’re going to find out.”) Trump seems also to regard nuclear weapons as an option of last resort in a wider range of contingencies (in line with current US policy), calling them “an absolute last step.” Elsewhere he has said, “Nobody is going to mess with us. But I would be very, very slow on the draw.”

Despite his longstanding interest in the issue of nuclear weapons, some of Trump’s recent remarks could use some clarification. He has suggested that North Korean leader Kim Jong Un may not subscribe to rational deterrence, yet he also proposes that Japanese and South Korean nuclear weapons could deter and balance the threat from Pyongyang’s arsenal. He also ignores the potential risk of a costly and dangerous arms race in East Asia, which could include China and other neighboring states, should Japan and South Korea head in this direction.

The liberal hawk. Like Trump, Hillary Clinton has listed nuclear proliferation and nuclear terrorism as the most threatening issues (or among the most threatening) confronting the United States—as far back as 2003—and has worked personally on these issues throughout her career.

As a senator from 2001 to 2009, Clinton criticized what she saw as the Bush administration’s significant failures on nuclear policy. Specifically, she focused on the dangers of weakening US support for the Comprehensive Nuclear Test Ban Treaty, the Nuclear Non-Proliferation Treaty, and the International Atomic Energy Agency. Clinton was also a vocal advocate for the Nunn-Lugar initiative to increase security for nuclear material and a critic of President Bush for not doing enough on these significant issues. Running for president in 2007, she made overcoming these failures central to her message and pledged to strengthen the necessary institutions and alliances key to combatting proliferation and the threat from WMD terrorism, positions she has recommitted to in her current campaign.

Clinton also addressed the threats emanating from Iran and North Korea, and their links to terrorism and the nuclear black market. As a senator, she consistently voted for sanctions to pressure Iran to give up its weapons ambitions. She introduced the Dirty Bomb Prevention Act, designed to decrease the availability of and access to radiological materials, and cosponsored the Nuclear Facility and Material Security Act, intended to improve safety and security measures at national nuclear facilities. She has been explicit in keeping “all options on the table” to ensure that Iran does not go nuclear—a significant position for a candidate whose 2002 vote for the Iraq War showed she was ready to use military force as a counter-proliferation tool.

As secretary of state from 2009 to 2013, Clinton continued to elevate nuclear proliferation as among her highest priorities. Alongside President Obama, she led the global efforts to pressure Iran to the negotiating table by designing one of the toughest international sanctions campaigns in recent history, and by authorizing the secret US-Iranian diplomatic channel in Oman that preceded the ultimately successful negotiations. This effort culminated in 2015 with Iran shipping out its stocks of enriched uranium, dramatically decreasing the number of operating centrifuges, foreclosing the plutonium pathway, and reducing the likelihood of a clandestine nuclear weapons program in Iran for at least 10 to 15 years. Clinton has also underscored how this diplomatic solution—backed by a combination of pressure and engagement—has not only blocked Iran’s path to the Bomb but has also prevented what might have turned into a dangerous regional arms race.

Likewise, she has focused on the threat emanating from North Korea. This was one aspect of Obama’s pivot to Asia—working to prevent the spread of WMD regionally and beyond. The challenge is familiar to Clinton—it was Bill Clinton whose efforts to prevent North Korea’s nuclearization in the early 1990s led to the Agreed Framework, which blocked the Kim regime’s plutonium pathway for more than a decade, avoiding what might have been a costly war. In her 2003 book Living History, Clinton articulated the dangers North Korea posed both as a proliferation risk itself, but also as a black-market actor, poised to sell “the world’s most lethal substance to the highest bidder.” As secretary of state, Clinton urged sanctions following repeated provocations and nuclear advancements, as well as regional pressure through an augmented US military presence.  

Finally, Clinton provided critical support for the rest of Obama’s nuclear security initiative, the so-called “Prague Agenda.” She also worked to secure the 2010 New START agreement, bringing Russian and American arsenals down to their lowest size in decades, and reinstating vital verification measures that had previously lapsed. In particular, as she wrote in Hard Choices, she used her congressional connections to secure key Republican votes needed to ensure treaty ratification. Prior to the 2008 election, she argued that “taking dramatic steps to reduce our nuclear arsenal would build support for the coalitions we need to address the threat of nuclear proliferation.” A President Clinton would likely continue efforts on nuclear security, seek opportunities to reengage on arms control with Russia, and take a tough or tougher line with Iran and North Korea. Her most recent comments—“any nation or group that supports or enables terrorist efforts to obtain or use weapons of mass destruction will be held accountable”—suggest she would pay more attention to state-based sponsorship than Obama has recently. There may also be a more limited focus on the effort to eliminate all nuclear weapons worldwide.

The rest of the pack. Fewer positions are attributable to Cruz, Sanders, and John Kasich since they have said and written much less about nuclear matters—both during and prior to their presidential campaigns. Cruz’s short political tenure (three years as a US senator) and lack of foreign policy focus means that much of what exists reflects current debates over Iran and nuclear modernization. Kasich, the governor of Ohio since 2010, is described as a budget-conscious defense hawk, but he too has focused little on nuclear affairs. And Bernie Sanders, despite a lengthy political career, including a quarter-century in the House and the Senate, has largely prioritized domestic topics, leaving him vulnerable to criticisms of foreign policy ignorance and inexperience. (Exceptions to this would include significant work on veterans’ affairs and, more relevant here, engagement on the domestic energy, climate, and industrial aspects of nuclear power, as overseen by the Senate Subcommittee on Clean Air and Nuclear Safety, of which he is a member.) Nevertheless, it’s worth recording what we do know about each of these other three candidates.

On his website, Cruz lists six pillars for securing America and defending the nation. The sixth is ripping up the Iran deal. Cruz has said his position is motivated by a lack of “anytime—anywhere” inspections and by the potential for a monetary windfall emboldening the Iranian regime. Cruz’s hostility, though, precedes the deal’s implementation: In March 2015, he joined 46 fellow senators in signing a letter to Iran describing the deal as simply an executive order—subject to review, modification, or termination under the next administration. Cruz also introduced the Sanction Iran, Safeguard America Act to further pressure Iran and complicate efforts to ensure the deal’s implementation. He introduced a resolution in 2015 designating the powerful Iranian Revolutionary Guard Corps as a terrorist organization. (Clinton co-sponsored a similar resolution in 2007.) Cruz recently endorsed a 10-year extension of the Iran Sanctions Act, and has supported other measures designed to undermine the negotiated solution.

Regarding the potential challenge from North Korean nuclear weapons, Cruz has described how the regime in Pyongyang is not suicidal and subscribes to some notion of rational deterrence. Subsequently, this February, he left the campaign trail for Washington to cast a vote in favor of a new round of missile-related sanctions. Despite voicing similar concerns, Sanders did not return to vote. Elsewhere on the Republican side, Kasich called for a harder line on North Korea. Beyond Iran and North Korea, Cruz has indicated his support for ballistic missile defense and nuclear modernization, as noted above.

According to Sanders, a nuclear-armed Iran threatens to further destabilize the Middle East and spur a dangerous arms race. Generally preferring negotiated, multilateral solutions, Sanders, in contrast to many Republicans, views the 2015 deal as the best option for forestalling a nuclear-armed Iran. Sanders is also the only candidate on either side of the aisle who has not vocally advocated for the use of force as a possible counter-proliferation strategy. Even Kasich, who has criticized those who would end the deal on day one, saying they were “inexperienced” and “playing to a crowd,” said that “if we think they’re getting close to … developing a nuclear weapon… you better believe that I would do everything in my power as the commander-in-chief to stop them from have a nuclear weapon.” Sanders also voted against the Iraq War, despite its intended goal of preventing Iraqi nuclear acquisition. Like Clinton, Sanders endorses the notion of a world without nuclear weapons. He has voiced skepticism with the current $1 trillion modernization plan, and may be likely to oppose such efforts going forward. Conversely, Kasich supports the modernization effort—despite being a known defense hawk and favoring balanced budgets in Ohio and Washington.

It’s also worth noting that in 2009 Sanders voted in favor of New START. In 2002, when still in the House, he voted to prohibit the use of defense funds for new nuclear weapons as well as to remove funding for space-based missile defense from a Pentagon appropriations bill. Around the same time, Clinton voted to shift funds allocated for missile defense to nonproliferation efforts instead.

Room for improvement. What are we to make of all of this? It is clear that Trump has been thinking about nuclear issues far longer than his current presidential bid. It is perhaps curious, then, given the accusations of foreign policy inexperience and ignorance that his competitors have levied, that he has not raised his well-documented positions. This seems especially perplexing in light of the fact that his main rival’s expertise amounts to three short years as a senator. One potential explanation for Trump’s relative silence is that his and Cruz’s positions on nuclear matters seem more similar than distinct: To varying degrees, both have criticized the deal with Iran; both see potential in using nuclear weapons against ISIS and perhaps elsewhere; and both focus on state-based nuclear threats from Iran and North Korea. There are differences, though. Cruz sees North Korea as rationally deterred, while Trump disagrees. Cruz (along with Kasich) has supported missile defense, which Trump has opposed—though not because it couldn’t work, but rather, in an echo of his fears from the 1980s, because “in this age of miniaturization, our real threat is not going to be flying in on a missile. It’s going to be delivered in a van, or a suitcase, or a fire-hydrant sized canister.” If there is more to the similarities than the differences, highlighting nuclear issues may be unhelpful for Trump. Given that neither Cruz nor Trump has demonstrated much penchant for nuance on the campaign trail, this may be unsurprising—particularly in light of the extremely small constituencies familiar with the details of nuclear policy. One further possibility is that even Trump, for whom very little seems sacred, sees nuclear rhetoric as very high stakes.

Despite an overcrowded domestic and international landscape, nuclear policy should still occupy a central place on every candidate’s agenda, as Clinton herself has said. The few remaining candidates hold different views on critical issues, including proliferation, security, and the role of nuclear weapons in the US military apparatus. While Trump may have been thinking about nuclear matters the longest (at least according to available records), he has not yet come out in support of a world without nuclear weapons. While Clinton advocated repeatedly for the use of force as a counter-proliferation strategy, she has most recently backed the use of force as a signal of credibility and strength undergirding the Iran deal’s diplomatic solution. Regardless of how one feels about the deal, it is likely that only a Clinton or Sanders presidency would keep it firmly in place; the Republicans have all voiced some opposition, though it’s unclear how quickly the deal itself could be annulled or modified. While Sanders is the most likely candidate to veto US nuclear modernization plans, only Cruz and Trump have explained how they could envision using nuclear weapons in a future conflict.

Clearly the candidates from both major parties leave much to be desired in their positions on nuclear issues. Individually and collectively, these positions are far too superficial for people hoping to occupy the Oval Office. Given the stakes, the nuclear portfolio demands much more than the cursory treatment it presently receives.