The post–Cold War world continues to provide the U.S. with a myriad of dynamic threats, from Iran’s increased aspirations to acquire nuclear weapons capability to Russia’s belligerence in Eastern Europe. With the current and growing number of potential threats to the U.S. and its allies, U.S. nuclear deterrence remains paramount to overall security in the face of international realities.

Keith B. Payne, director of the Graduate School of Defense and Strategic Studies at Missouri State University and former deputy assistant secretary of defense, writes that opponents of U.S. nuclear deterrence fail to understand the harsh international realities when developing their perceptions of the international security environment. “In the arena of nuclear policies, the risks of favoring feel-good ideology over reality could not be higher,” says Payne.

Critics of U.S. nuclear deterrence wrongfully believe that U.S. nuclear deterrence is an archaic product of the Cold War and is no longer applicable to today’s security environment. They call for mass reductions in U.S. nuclear weapons, citing security differences between the Cold War and today—the Cold War being characterized by the existential nuclear threat posed by the Soviet Union with modern-day Russia mistakenly seen as a partner of the U.S. Kim Holmes, distinguished fellow from The Heritage Foundation, details the similarities between the Cold War and the current international order.

Threats to U.S. national security remain. Although no longer the Soviet Union, Russia continues to assert its power and attempts to regain its prestige as a world superpower. Russia’s aggressive involvement in Crimea and Eastern Europe shows that Russia cares little for international law or national sovereignty. Additionally, Russia has violated the Intermediate-Range Nuclear Forces Treaty. The New Strategic Arms Reduction Treaty (New START), itself, hinders U.S. security. According to the State Department, Russia now has more actively deployed strategic warheads than the U.S.

Critics of current U.S. nuclear deterrence also argue that U.S. superior conventional forces are sufficient to maintain security. The argument is obviously flawed. For one, sequestration will hinder U.S. ability to maintain superior conventional forces in all areas of the world, in the face of the numerous potential crises that may arise. Additionally, defense budget cuts have further weakened the quantity and capacity of conventional forces.

The Obama Administration should fund the nuclear weapons budget that it had originally promised to finance before the New START ratification. For the fiscal year (FY) 2015 request, the Obama Administration requested $8.3 billion for the National Nuclear Security Administration’s weapons activity programs. Originally, the Obama Administration had committed to requesting $8.7 billion for FY 2015. An inadequate budget hinders U.S. nuclear weapon capability and delays modernization efforts. The U.S. cannot leave its military in a position where it cannot fulfill U.S. security commitments around the world because its capabilities, training, and platforms deteriorate.

Steve Smolinsky is currently a member of the Young Leaders Program at The Heritage Foundation. For more information on interning at Heritage, please click here.