Policy & Advocacy

Backgrounder on Nuclear Arms, September 2015

Year Published
  • 2015
  • English

“A world without nuclear weapons” is a goal shared by all nations and echoed by world leaders, as well as the aspiration of millions of men and women. The future and the survival of the human family hinges on moving beyond this ideal and ensuring that it becomes a reality. -- Pope Francis, December 7, 2014

In 1963 Saint John XXII wrote in Pacem in Terris: “Nuclear weapons must be banned. A general agreement must be reached on a suitable disarmament program, with an effective system of mutual control.” Support for nuclear disarmament and non-proliferation has been emphasized by Paul VI, Saint John Paul II, Benedict XVI and Francis. The U.S. Bishops have worked for nuclear disarmament and non-proliferation for decades.

Nuclear Non-Proliferation Treaty: The Nuclear Non-Proliferation Treaty (NPT) is the cornerstone of global efforts to curb and reverse the spread of nuclear weapons. 198 countries have ratified the treaty, including the five acknowledged nuclear powers: United States, Russia, United Kingdom, France, and China. Only four nations have not: India, Israel, Pakistan and North Korea. The NPT prohibits non-nuclear states from acquiring nuclear weapons (non-proliferation), requires nuclear states to reduce and eliminate nuclear weapons (disarmament), and guarantees access to peaceful nuclear technology (nuclear power).

Years ago President Ronald Reagan and General Secretary Mikhail Gorbachev called for abolishing all nuclear weapons. More recently, former Secretaries of State and Defense George Shultz, William Perry and Henry Kissinger and Senator Sam Nunn have promoted a nuclear-free world. President Barack Obama and then Russian President Dmitry Medvedev committed “our two countries to achieving a nuclear free world.”

New START Treaty: In 1991, the United States and Soviet Union ratified the Strategic Arms Reduction Treaty (START). This treaty limited the number of nuclear warheads and delivery vehicles (missiles and bombers) that each country could deploy. The treaty also incorporated a solid set of verification measures the two nations could use to monitor each other’s nuclear arsenals and compliance with the treaty.

Today the United States and Russia still hold about 90% of all nuclear weapons, large arsenals left over from the Cold War. START expired on December 5, 2009 and with it the verification protocols, but both nations agreed to keep its provisions in effect while they negotiated a START follow-on treaty. Implementation of a New START Treaty was critical because verification ensures transparency and even modest reductions in the number of weapons can set the stage for future reductions. President Obama and President Medvedev of Russia signed a new Strategic Arms Reduction Treaty (New START) on April 8, 2010. The New START Treaty reduces deployed strategic warheads to 1550, 30 percent below the existing ceiling; limits both nations to no more than 700 delivery vehicles; and includes new verification requirements. In December 2010 the New START Treaty was ratified by the Senate on a solid bipartisan vote of 71 to 26.

Comprehensive Test Ban Treaty: Despite U.S. involvement in initiating the negotiations, in 1999, the U.S. Senate failed to ratify the Comprehensive Test Ban Treaty (CTBT) that would stop nuclear testing. Some Senators who voted “no” expressed concerns about the ability of the United States to maintain its arsenal in the absence of testing and others were concerned about verifying compliance with the treaty. Prominent scientists have argued that the U.S. can safely maintain its nuclear arsenal without testing and that the ability of the international community to verify compliance is amply demonstrated by detections of tests in North Korea. The Obama Administration supports ratification of this treaty that 151other nations have ratified (including UK, France, and Russia). It is not known when the CTBT may be submitted to the Senate for ratification.

P5+1 Agreement with Iran: In recent years, serious questions have been raised regarding Iran's nuclear program. In response there were sweeping international sanctions and talk of military intervention. The sanctions have had a crippling effect on that nation's economy and on the lives of ordinary Iranians. The election of Iranian President Rouhani created an opening for renewed diplomatic efforts so the P5+1 entered into negotiations with Iran regarding its nuclear program and international sanctions.

In July 2015, the United States and its P5+1 partners reached an agreement with Iran that aims to curb Iran's development of nuclear weapons while allowing the use of nuclear energy for peaceful purposes. It took 20 months of concerted collaboration by the United States, United Kingdom, Russia, China, Germany and France (P5+1) to reach this agreement with Iran. In September, a cloture vote in the Senate that would have allowed rejection of the P5+1 deal failed, so the agreement stands.

USCCB POSITION: The United States and other nuclear powers must move away from reliance on nuclear weapons for security. A global ban is more than a moral ideal; it should be a policy goal. As with other nuclear reductions treaties, USCCB advocated for ratification of the New START Treaty in 2010.

USCCB has urged the Administration and Congress to view arms control treaties not as ends in themselves but as steps along the way to achieving the goal of a mutual, verifiable global ban on nuclear weapons. Much deeper, more irreversible cuts, in both strategic and tactical weapons, are both possible and necessary.

USCCB plans to support Senate ratification of the CTBT if and when it is introduced. The Church opposes the use of nuclear weapons, especially against non-nuclear threats, and the development of new nuclear weapons. The Church urges that nuclear deterrence be replaced with concrete measures of disarmament based on dialogue and multilateral negotiations. In its nuclear policy the U.S. should commit to never use nuclear weapons first and to reject use of nuclear weapons to deter non-nuclear threats.

Since 2007, the USCCB Committee on International Justice and Peace, reflecting the longstanding position of the Holy See, has urged our nation to pursue diplomacy to ensure Iran's compliance with its obligations under the Nuclear Non-Proliferation Treaty. In the wake of the P5+1 Agreement with Iran, Bishop Oscar Cantú, Chair of the Committee on International Justice and Peace, wrote in a letter to Congress, this multinational agreement was "no small achievement."

A diplomatic solution with Iran is much preferable to military action, which would have unpredictable and dramatic repercussions for the region. In January 2015, Pope Francis said, "I express my hope that a definitive agreement may soon be reached between Iran and the P5+1 Group regarding the use of nuclear energy for peaceful purposes, and my appreciation of the efforts already made in this regard." The Holy See views the P5+1 Agreement with Iran "in a positive light," expressing the hope that the fruits of the agreement "will not be limited" to nuclear issues, "but may indeed extend further." The Church does not weigh in on the technical details of the agreement, but has consulted with many experts on the broad outlines required for a credible and verifiable agreement that gradually builds trust.

The key moral question for the Church remains: Is it preferable to resolve differences through dialogue and negotiation, or to resort to coercion and armed force? Six major nations have chosen the path of dialogue to resolve the serious questions about Iran’s nuclear program. Bishop Cantú urged “Congress to endorse the result of these intense negotiations because the alternative leads toward armed conflict, an outcome of profound concern to the Church."


  1. If it is introduced, urge Senators to support ratification of the Comprehensive Test Ban Treaty (CTBT).
  2. Please encourage Congress not to take any actions that could undermine the agreement between the P5+1 and Iran.

For further information: visit https://www.usccb.org/issues-and-action/human-life-and-dignity/war-and-peace/nuclear-weapons/index.cfm or contact Stephen Colecchi, Director, Office of International Justice and Peace, USCCB, 202-541-3196 (phone), 202-541-3339 (fax), scolecchi@usccb.org.

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