Back when the greatest threat to mankind was a nuclear war between the United States and the Soviet Union, an arms reduction agreement between America and Russia was a big deal. But now that a nuclear weapon falling into the hands of a terrorist group or rogue state looks like a more likely catastrophe, superpower arms reduction talks don’t grab the same amount of attention they once did. But they should.

Even though Russia is not our adversary the way that the Soviet Union was, both countries still have substantial arsenals of weapons that are pointed at each other. There is improved communication between military authorities of the two countries, but there have been close calls anyway in the post-Soviet era when missiles were nearly launched in response to what was mistakenly read as an attack.

In addition, both the United States and Russia need to work together for non-proliferation efforts to be a success. If a weapon is likely to fall into the wrong hands, it would be likely to fall from one of these two biggest arsenals, so reducing their sizes makes sense. And by setting an example, the two former enemies will have more leverage with smaller countries that want to join the nuclear club.

The most notable is Iran, whose nuclear ambition is a major focus of the Obama administration’s foreign policy. Russia, Iran’s neighbor and sometimes friend, has influence in that country that the United States does not.

The administration reports that this reduction, which is smaller than the one negotiated by President George W. Bush in 2002, is just a first step. It should lead to another round of talks that cuts stockpiles even further, including stored weapons, and future rounds of talks that include other nuclear powers like France and China. Following the signing ceremony in April, Obama will convene a meeting of 45 heads of state to discuss the security of nuclear material. It would be the largest summit ever convened by a U.S. president.

Even after the Cold War, nuclear weapons remain a major threat to the world’s security. That’s why a treaty between the United States and Russia remains a very big deal.