Thank you, Chairman Corker, Senator Cardin and Members of the Committee.

It is always a great honor for me to come before this Committee and I am very happy to update you on this Administration’s nuclear nonproliferation efforts, and the role of the Nuclear Security Summit process in preventing nuclear terrorism. These are critically important issues for our nation and for the world, so I thank you for your interest.

This administration came into office with nuclear nonproliferation as a critical component of our foreign policy. In 2009, President Obama called for a series of concrete steps to help protect our country, and the world, from nuclear dangers.

We’ve taken steps to verifiably reduce the number of nuclear weapons that are deployed against us, as we continue to maintain a safe, secure and effective arsenal for as long as nuclear weapons exist.

I am glad to tell you that the New START Treaty, with the bipartisan support of this body, is providing predictability about the Russian nuclear arsenal at a time of continuing crisis and very poor relations with Moscow. The Treaty is thus manifestly in the interest of U.S. national security.

In this hearing, I will not further focus on arms reductions, but on the steps we have taken to protect against the further spread of nuclear weapons and the threat of nuclear terrorism.

Among those steps has been turning the Proliferation Security Initiative and the Global Initiative to Combat Nuclear Terrorism into durable international institutions—increasing their membership and enhancing coordination to stop shipments of WMD and related items, as well as helping partner nations prevent dangerous nuclear materials from falling into the hands of criminals or terrorists. We have also helped to strengthen the International Atomic Energy Agency’s (IAEA) safeguards system to ensure nuclear programs around the world are purely peaceful.

And earlier this year, the IAEA confirmed that Iran had completed its nuclear commitments to reach “Implementation Day” of Joint Comprehensive Plan of Action (JCPOA) reached between the P5+1, the European Union, and Iran, closing off all of Iran’s pathways to acquire enough fissile material for a nuclear weapon. As it is fully implemented, the agreement is healing a major wound in the global nonproliferation regime.

Yet the prospect of nuclear terrorism presents a very different challenge from proliferation by other countries. Terrorists do not make commitments, other than to destruction, and the black markets and smuggling networks that could link them with nuclear materials are not bound by recognized rules, norms, or borders. Given the destruction that terrorists could unleash with only one weapon, nuclear terrorism is the greatest threat to our national security.

In order to marshal unprecedented attention and efforts to address this threat, the Administration initiated the Nuclear Security Summit process in 2010, bringing together leaders from 50+ countries and four international organizations. The fourth and final of these Summits will be held March 31 and April 1 in Washington, D.C.

Through these Summits, the international community has strengthened the international organizations, institutions and multilateral legal instruments that make up the global nuclear security architecture.

Summit participants have also pledged to work together in building capabilities to prevent, detect, and respond to radiological and nuclear smuggling threats. We all recognize the urgent imperative of collective action to find, arrest, and prosecute nuclear smugglers and their networks, and recover any dangerous nuclear or radioactive materials that remain out of regulatory control.

The Summit process hasn’t just been a matter of gathering leaders to meet every two years. Its achievements are measured by the practical follow-through of tangible, real-world actions making vulnerable nuclear material secure, kilogram by kilogram, fence by fence, and guard by guard.

Simple, but critical steps, such as bolstering security at facilities with nuclear and radioactive material, are paying dividends.

As Assistant Secretary Countryman will outline in greater detail, we have expanded our ability to help international partners prevent, detect and respond to trafficking in nuclear and other radioactive material.

At the 2016 Summit, leaders will highlight the accomplishments that have been made and commit to the further expansion and strengthening of the global nuclear security architecture.

Summit participants will commit to maintaining the momentum of the Summit process after 2016, including through implementing Action Plans for five key international organizations and initiatives: the UN, the IAEA, INTERPOL, Global Partnership, and the Global Initiative to Combat Nuclear Terrorism.

Looking ahead, we hope to continue to work closely with Congress to further strengthen the global nonproliferation regime. Assistant Secretary Countryman and I are happy to outline specific efforts such as the improvement of verification and monitoring capacities, including ensuring that the IAEA is fully resourced, or demonstrating our support for nuclear weapons-free zones.

Mr. Chairman, Senator Cardin and Members of the Committee, we should be under no illusions about the enormous nuclear proliferation challenges we face, but looking ahead, we know that the price of freedom from nuclear terrorism is eternal vigilance. If we don’t get this right, nothing else really matters.

I am certain that with your support, the United States will have the tools we need to meet these challenges.

I want to again thank the Committee and its leaders for your attention and interest in these matters and your dedication and commitment to enhancing American national security.

I look forward to your questions.

Thank you.