Editor's Note: (Nickolas Roth is a research associate at the Project on Managing the Atom in the Belfer Center for Science and International Affairs at Harvard Kennedy School. Follow him on Twitter: @Nickolas_Roth. The opinions expressed in this commentary are his.)
(CNN) Hillary Clinton and Donald Trump are once again trading barbs over who has the right disposition to be president -- including who is best suited to have a "finger on the button."
It is, of course, not unusual for candidates to critique each other's qualifications. But there is a good reason why assessing the candidates' judgment and temperament is particularly important: The president of the United States has complete authority over more than 1,000 nuclear weapons ready to launch.
The reality is that miscalculation or miscommunication with another country could result in catastrophe. This is true at any time, but whoever is elected in November will assume office during a period when the risk of nuclear confrontation between the United States and Russia may be higher than it has been in decades.
Both NATO and Russia have significantly bolstered their military presence and activities in Eastern Europe, increasing the likelihood of a direct conflict between the two sides. Indeed, every military exercise and every near miss between a Russian jet and a U.S. warship is potentially a crisis in the making.
The United States and Russia have a long history of negotiated arms control agreements designed to manage nuclear weapons risks. But they also continue to pose an existential threat to one another. Each country targets the other with hundreds of nuclear weapons that can be fired minutes after the order is made and, during a crisis, both sides have strong incentives to be the first to launch a nuclear strike.
Further compounding the danger is the fact that Russia lacks effective early-warning systems to help identify whether a nuclear attack is actually occurring. If this sounds like a Stanley Kubrick fantasy, it isn't. In 1995, Russian radars indicated a Norwegian weather rocket might be a nuclear missile heading for Russia, and staff prepared Russian President Boris Yeltsin's nuclear command briefcase for possible retaliation (which fortunately did not occur).
If this had happened during a major crisis, there is no telling what could have happened. The probability of a substantial false alarm coming in the midst of a major crisis may be low, but the potential consequences are the destruction of most of human civilization, so action to reduce even low probabilities is justified.
Given such risks, the next president will need to find a balance between assertively protecting U.S. interests against Russian encroachments and exercising restraint so as to avoid potentially nuclear crises and itchy Russian trigger fingers. Getting the balance wrong could mean stumbling into unintended nuclear confrontation. This is a dauntingly difficult task, and will require new thinking.
For the past 20 years, despite the end of the Cold War, the United States has maintained high-risk nuclear weapons policies in part because U.S.-Russian relations were relatively good and a nuclear crisis seemed implausible. This dynamic has now changed -- there is significantly less margin of error for provocative nuclear policies today than at any time since the end of the Cold War.
With that in mind, policies that emphasize predictability, transparency and restraint are now needed to reduce the risk that a miscalculation or accident will lead to the use of nuclear weapons.
In practice, that means the United States and Russia should continue to observe and strengthen existing arms control agreements. But further steps are needed, as well. U.S and Russian nuclear weapons should be removed from "hair trigger" alert status, which currently allows both countries to launch a nuclear attack on short notice.
The decision to kill potentially millions in a nuclear strike requires careful thought, as much information as possible, and more than a few short minutes. This step should be taken in tandem with reciprocal pledges that neither side will be the first to use nuclear weapons against the other.
In addition, the United States and Russia should begin serious discussions of how each can defend itself from tiny missile forces from countries like Iran and North Korea without giving the other a motive to build up its own offensive forces to maintain its deterrent, or creating new incentives for striking first in a crisis.
In 2002, the United States withdrew from the Anti-Ballistic Missile Treaty arguing it was no longer needed, in part, because the Cold War was over. It is now time to find a way to restore the stability that the treaty provided.
In the coming months, U.S. presidential candidates must articulate a comprehensive plan for nuclear risk reduction. Not only should this include ideas for decreasing the likelihood of nuclear conflict between the United States and Russia, but the candidates must also demonstrate that they have the judgment and thoughtfulness that will make disputes with Russia less dangerous when they inevitably arise.
Americans and Russians made it through the Cold War because of rational leadership, restraint, policies that increased predictability and transparency and a lot of luck. The next president will need to rely on all of these in order to avert a nuclear disaster with Russia. Sober judgment will be essential. That's a fact that voters should keep in mind in November.
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