Michael A. Levi says that when it comes to Iranian nuclear capability, "Distinctions between zero, limited and robust enrichment, and between all of these and a nuclear-armed Iran, really matter."

Matthew Kroenig argues that the world will not be safer if the United States had no nuclear weapons.

Emma L. Belcher recommends strengthening the Proliferation Security Initiative and adopting its model for other agreements in order to advance U.S. interests in preventing proliferation and provide a useful framework to mobilize international action on important global issues.

Emma L. Belcher recommends the establishment of a nuclear security fund to which the private sector could contribute in order to help build nuclear security capacity worldwide.

Stephen Sestanovich testifies before the U.S. House Foreign Affairs Committee that, though the U.S. and Russia restored broadly cooperative ties after 2008, the relationship is marked by lingering frustration and even friction.

Is reducing the world's nuclear arsenals to zero possible, or even desirable?

Emma L. Belcher says the recent detterence of a North Korean ship carrying nuclear material highlights the need for criminal codes that take nuclear crimes seriously.

Suzanne Maloney and Ray Takeyh say Mahmoud Ahmadinejad is being sidelined by religious fundamentalists in Iran, and it's bad news for American officials seeking to halt Iran's nuclear program.

UN Security Council Resolution 1985 regarding North Korea was adopted by the UN Security Council on June 10, 2011.

UN Security Council Resolution 1984 regarding Iran was adopted by the UN Security Council on June 9, 2011.

At their meeting in Deauville May 25, Russian President Medvedev and U.S. President Obama remained stalled on missile defense cooperation and Russia's bid to join the WTO, says CFR's Stephen Sestanovich.

The events convulsing the Middle East should prompt supplier states to place a moratorium on most nuclear cooperation with the region and devise long-term plans for better safeguarding major nuclear sites around the world, writes CFR's Jonathan Pearl.

In his new book, Weak Links: Fragile States, Global Threats, and International Security, Stewart Patrick argues that most fragile states are not a threat to the United States.

Leslie H. Gelb reviews The Age of Deception, by Mohamed El Baradei.

As former president Jimmy Carter visits Pyongyang, any movement on resumption of stalled talks on North Korea's denuclearization is unlikely, says CFR fellow Sue Terry. Washington should continue to deter Pyongyang's aggressive behavior using sanctions and working with regional allies, she says.

Matthew Fuhrmann examines the consequences and effectiveness of military strikes against nuclear facilities.

A summit hosted by the Obama administration one year ago has spurred momentum on global nuclear security measures. But the United States must lead efforts to redouble commitments on preventing the proliferation of nuclear materials, writes CFR's Emma Belcher.

Writing for the Washington Post, Nicholas Eberstadt argues that for all of its many weaknesses, North Korea employs a coherent and consistent strategy for nuclear negotiations.

Clive Cookson breaks down the situation at Japan's Fukushima plant and the implications for the future of the nuclear industry.