SORRY TO disappoint thriller fans, but in real life, there is no nuclear button. The president’s command and control over nuclear forces is more sophisticated than that. House Speaker Nancy Pelosi (D-Calif.) called attention to this Cold War system last week, as she voiced worries about President Trump’s erratic behavior. Mr. Trump will be out of office soon, but there are long-overdue reforms that would reduce the dangers by taking nuclear weapons off launch-ready alert. Congress and President-elect Joe Biden ought to examine them.

In the name of deterrence during the Cold War, both the United States and Soviet Union aimed nuclear-armed missiles at each other, the “cocked pistols” of mutually assured destruction. Intercontinental ballistic missiles fly across the oceans in 30 minutes, so a president might have only minutes to decide whether to retaliate, and how. To facilitate such an agonizing decision in an emergency, an aide follows the president everywhere carrying the so-called nuclear football, containing the communications links and launch procedures. A portion of U.S. strategic forces — land- and some sea-based missiles — is on launch-ready alert. Ground-based missiles can be launched within about four minutes of the president’s order, sea-based within 12 minutes or so.

In an emergency, a president first authenticates himself using a code, then picks from options prepared in advance. The order would be transmitted to a Pentagon command center to be carried out. Legally, the president has the sole authority to do this. The options before the commander in chief would have been vetted for legality. Obviously, in such an emergency, there is no time for a Cabinet meeting or consultation with Congress. The whole system is designed to be streamlined and the process short.

But the process is not black-and-white. There is always a human factor. If a president issued an order to launch nuclear weapons while the country was at peace and not under nuclear attack, a duty officer in the command center might well question why. Others in the military probably would, too. Another scenario, more worrisome: What if a president was in the middle of a chaotic, non-nuclear war and impulsively decided to escalate to nuclear? Chain of command and military discipline are essential. But so is common sense of those involved.

Opportunities exist today for Congress and Mr. Biden to reduce the nuclear danger. Both Russia and the United States could take nuclear missiles off launch-ready alert, or at least find ways to lengthen the time a president has to make a decision and reduce the chances of a catastrophic miscalculation. While Russia remains adversarial, the relationship today does not warrant a nuclear-alert posture created for a Cold War that ended three decades ago. Any change in alert procedures must be negotiated bilaterally with Russia, and verifiable, but both countries would benefit from backing away from the precipice. There are signs, still tentative, that China is inching toward higher alert levels for some of its nuclear forces. It would be smart for all three nations to retreat from the Cold War madness of hair-trigger alert.

Read more: