Iran invites China to inspect its nuclear facilities.

The United States and China sign a deal to build a jointly-run nuclear security center in China. This center will be dedicated to preventing proliferation.

Belarus and Russia begin talks on a deal to build a Russian nuclear power plant in Belarus. 

Saudi Arabia announces a deal with Areva to begin using nuclear power in place of some fossil fuels in the country. 

North Korea approaches South Korea to indicate it wants to continue six-party talks concerning North Korean nuclear facilities once again. 

Tokyo's Governor Shintaro Ishihara makes a public declaration that Japan should acquire nuclear weapons to counter the threat of a nuclear China.

United States Secretary of State Hillary Clinton and Russian Foreign Minister Sergei Lavrov exchange instruments of ratification for New START, causing the treaty to officially take effect.

Russia calls on the United States to remove all nuclear weapons from foreign soil, especially in Europe.

Iran test-launches the "Persian Gulf," a ballistic missile capable of traveling 185 miles. 

Satellite imagery appears indicating that Pakistan is building a fourth nuclear reactor. 

Iran declares itself a nuclear state at a parade celebrating the 31st anniversary of the Iranian Revolution.

A 9.0 earthquake and subsequent tsunami strike Japan, causing the Fukushima Daiichi Nuclear Power Plant to shut down. Emergency cooling systems fail, causing the plant to experience partial meltdown. The crisis is labeled at the highest level on the International Nuclear Events Scale, meaning there is a "major release of radioactive material with widespread health and environmental effects."

Malaysian police discover parts designed for nuclear weapons being smuggled on board a ship to Iran.

Japanese Prime Minister Naoto Kan announces that his nation will lead the world in renewable energy and wean itself off nuclear power. He dubs his goals as the "Sunrise Project," and deems that 20% of all Japan's energy will be from entirely renewable sources by 2030.

Pakistan tests the HATF IX short range tactical nuclear missile. The missile is designed to detonate a low-yield nuclear weapon, and was developed as a response to India’s "Cold Start Doctrine" that calls for rapid surprise attacks on Pakistan.

The push for ratification of the Comprehensive Test Ban Treaty in the United States begins again. President Barack Obama and Undersecretary of State for Arms Control Ellen Tauscher announce a new push for CTBT ratification in the coming months.

Russia delivers 30 tons of nuclear fuel to Iran, completing an agreement signed in 1995 between Iran and Russia to build a nuclear power facility. Russia has the expectation that Iran will return the spent fuel to prevent nuclear proliferation.

The emergency cooling system at Browns Ferry Nuclear Power Plant in Alabama fails inspection, leading to increased concern about the safety of nuclear energy in the United States.

It is revealed that 32 separate nuclear power plants in the United States have failed safety tests after the Fukushima incident. 

German Prime Minister Angela Merkel, in response to Japan’s nuclear meltdown at Fukushima Daiichi, announces a plan to end all nuclear power in Germany by 2022.

It is revealed that the United States gave "negative assistance" to France while pursuing advanced nuclear weapons in the 1970’s. This means that U.S. officials did not provide France with the technology for nuclear fission, but instead reviewed France's progress and told it whether it was on the right track.

Iran successfully completes a pilot launch of the Bushehr Nuclear Reactor.

The United Nations sends a team to the Fukushima Daichi power plant to investigate and prepare a report for the International Atomic Energy Agency meeting in June. 

Syria announces it is willing to fully comply with International Atomic Energy Agency (IAEA) demands to see the 2007 alleged nuclear site bombed by Israel. 

The United States, for the first time, releases detailed data about its nuclear weapons capacity. This information is shared as part of the New START Treaty. The U.S. declares 5,113 nuclear weapons. This does not include weapons awaiting dismantlement.

Japanese Prime Minister Naoto Kan survives a no-confidence vote after his slow response to the Fukushima Daiichi nuclear meltdown. Kan gained enough votes to remain Prime Minister by offering to quit in the next few months.

A low-level emergency is declared at the Omaha nuclear power plant in the United States. Rising water poses a risk to the nuclear power plant.

The International Atomic Energy Agency gives approval to Armenia's Metsamor reactor, despite the reactor being 35 years old and considered by many to be a disaster waiting to happen. 

Iran's Revolutionary Guard posts an article on their website entitled "The Day After the First Iranian Nuclear Test," stoking fears about Iran's nuclear program. 

The Swiss government votes to phase out nuclear energy in the country by 2034.

The International Atomic Energy Agency announced that the Fukushima Daiichi plant in Japan has experienced a "melt-through" at three reactors. Significantly more dangerous than a meltdown, a melt-through is considered the worst possible scenario short of an explosion at the nuclear plant. 

Iran announces to the International Atomic Energy Agency that it will begin enrichment at its new Fordow plant. 

The International Atomic Energy Agency (IAEA) reports Syria to the United Nations Security Council (UNSC) over its alleged nuclear program that was destroyed by Israeli planes in 2007. This is one of the first occasions the IAEA has not come to consensus, but instead reported Syria based upon majority rule. It marks the beginning of a major split in IAEA policy.  

Strontium-90 is found in the soil in areas around the damaged Fukushima Daiichi nuclear power plant in Japan. Strontium-90 has a half-life of 29 years and is known to cause leukemia.

Italy, following in the footsteps of neighboring Germany in the aftermath of the Fukushima Daiichi incident, votes overwhelmingly (95%) to end all plans for nuclear power in the country.Italy had previously eliminated its nuclear facilities in 1987.

The Oconee Nuclear Station in South Carolina becomes the first nuclear power plant in the United States to use digital controls. The transfer to digital controls took so long due to safety concerns of hackers infiltrating a nuclear plant.

Germany completes its first round of nuclear reactor shutdown, closing all older nuclear reactors in the country. 

The Tennessee Valley Authority signs a letter of intent for the purchase and development of miniature nuclear reactors. 

Japanese Minister for Economy Banri Kaeida publicly declares that Japanese nuclear reactors must go back online. He estimates that 11% of Japan's energy supply will be lost if nuclear reactors are shut down permanently.

A wildfire in New Mexico reaches the Los Alamos National Laboratory. The lab contains above-ground containers of plutonium that could ignite if the fire reaches them.

Saudi Arabia threatens to develop its own nuclear arsenal if Iran tests a nuclear weapon.

It is revealed that several Pakistani officials were bribed to reveal nuclear secrets. AQ Khan, famed founder of Pakistan’s nuclear program, is the one to make the allegations. The same day, he is ordered to high court for seemingly unrelated charges.

Lightning strikes the Nevada Nuclear Security Site where thousands of nuclear test detonations occurred. A fire ensued, and authorities were sent to contain any radiation from being released.

Funds are put in place to build a shelter over the Chernobyl nuclear reactor that experienced meltdown in 1986. This was proposed in response to the belief that Kiev, Ukraine is still being affected by the fallout from the reactor site.

Cruz Loya Alveres, an illegal immigrant in the United States, successfully enters the Palo Verde nuclear plant facilities with a fake ID as part of a construction crew. Alvares was arrested and did not make it to the restricted area of the site.

The Japanese government sends warnings to its population of radioactive beef as the fallout from Fukushima Daiichi continues. 

The Oyster Creek Nuclear Station in New Jersey is set this day to shut down in 2019. The nuclear plant was found to be damaging to aquatic wildlife in the area and, in exchange for not building costly cooling towers to prevent wildlife death, the plant operators agreed to close the plant early.

An Iranian scientist is assassinated in Tehran. He was believed to be working on Iran’s nuclear program, although the Iranian government denied this claim. This is the fourth attempted assassination on Iranian scientists in two years. Dozens of other Iranian scientists also died in plane crashes over this time period. 

A US Minuteman III nuclear missile test was launched from Vandenberg Air Force Base in California. The test was aborted after 5 minutes and the missile was destroyed over the Pacific Ocean. The cause of the failure was reported only as an unspecified “anomaly” that raised safety concerns.

General Electric successfully tests a method of enriching uranium with lasers. This new method is likely to be cheaper and less complicated than the traditional enrichment method involving thousands of finely tuned centrifuges. Non-proliferation experts have expressed concerns that laser enrichment could make it easier for countries to hide enrichment activities.

The annual General Conference of the IAEA ends in discord over a resolution titled "Strengthening the effectiveness and improving the efficiency of the safeguards system and application of the model additional protocol." Egypt, Iran and Cuba opposed the resolution. A Western diplomat claims that those three countries wanted to include language in the resolution to give the IAEA a role in nuclear disarmament.

The National Nuclear Security Administration (NNSA) and the Tennessee Valley Authority (TVA) announce a plan to increase tritium production by 50% at the Watts Bar "civilian" nuclear power plant. The tritium will be used in nuclear weapons.

The United Nations selects Finland to host a conference to discuss making the Middle East free of nuclear weapons and weapons of mass destruction on a date to be determined in 2012.

The UN General Assembly’s First Committee passed a resolution calling for the eradication of nuclear arms. The resolution received support from 156 nations, including 97 co-sponsors. Fourteen countries abstained, four of which possess nuclear weapon states: China, Israel, Pakistan, and India. North Korea was the only country to vote against the resolution.

EDF, France’s state-owned energy firm, is fined 1.5 million euros for spying on the anti-nuclear group Greenpeace. EDF is the world’s biggest nuclear energy supplier, and has been challenged for years by Greenpeace’s anti-nuclear energy campaigning.

The governor of Hiroshima prefecture, Hidehiko Yuzaki, says that he would like President Obama to visit Hiroshima, and that an apology for the US atomic bombing of the city in 1945 would not be necessary.

Russia announces plans to counter the missile defense system that the US has been planning in Europe. Russia insists on being involved in any missile defense activity in the region and is asking for an explicit legally-binding guarantee that the US missile defense system will not target Russia.

It is revealed that the United Kingdom is spending $3.1 billion on nuclear weapons plants before the country makes a decision on whether or not to replace its current fleet of four submarines that carry Trident nuclear warheads.

The U.S. State Department releases an updated count of its deployed and reserve strategic nuclear weapons as of September 1, 2011. The U.S. has 822 deployed ICBMs, SLBMs and heavy bombers, while Russia has 516. The number of nuclear warheads deployed on these platforms total 1,790 for the U.S. and 1,566 for Russia.

North Korean leader Kim Jong-il dies after suffering a heart attack. His son Kim Jong-un appears to be transitioning into power, and there is no indication that North Korea will abandon its nuclear program.

Fire engulfs a docked Russian nuclear submarine while it was undergoing maintenance. Nuclear weapons were apparently on board, but no damage to the weapons was reported.