Timeline of nuclear weapons development

• 1895 – Wilhelm Konrad Röntgen discovers X-rays at the University of Würzburg. • 1896 – Henri Becquerel discovers that uranium emits radiation at the National Museum of Natural History in Paris. • 1898 – J.J. Thomson observes the photoelectric effect. • 1900 – Max Planck theorizes that matter can only absorb energy in fixed quanta. • 1904 – Frederick Soddy first proposes a bomb powered by nuclear fission to the Royal Engineers. • 1905 – Albert Einstein proposes mass–energy equivalence, deriving from his theory of special relativity, which he had developed earlier that year. • 1911 – Ernest Rutherford discovers that the majority of the energy in an atom is contained in the nucleus through experiments at the University of Manchester. • 1912 – J.J. Thomson discovers isotopes through experiments with neon. • 1920 – Rutherford postulates the existence of a neutral particle in the atomic nucleus at a Bakerian Lecture in London. • 1924 – Writing for The Pall Mall Gazette, Winston Churchill speculates "Might a bomb no bigger than an orange be found to possess a secret power to destroy a whole block of buildings – nay to concentrate the force of a thousand tons of cordite and blast a township at a stroke?" ==1930–1940==

• 1932 – James Chadwick discovers the neutron, leading to experiments in which elements are bombarded with the new particle. • 1933 – Leó Szilárd realizes the concept of the nuclear chain reaction, although no such reaction was known at the time. He invented the idea of an atomic bomb in 1933 while crossing a London street in Russell Square. He patented it in 1934. (British patent 630,726) • 1934 – Enrico Fermi conducts experiments in which he exposes uranium and thorium to neutrons to create distinct new substances. Although he is unaware at the time, he creates the first synthetic elements, the transuranium elements. • 1938 – Fermi is awarded the Nobel Prize in Physics for his achievements, and flees from Fascist Italy to the United States due to the racial laws ratified under pressure from Nazi Germany. • 1938 – December – The German chemists Otto Hahn and Fritz Strassman detect barium after bombarding uranium with neutrons. This is correctly interpreted by Lise Meitner and her nephew Otto Robert Frisch as nuclear fission. • 1939 – January – Otto Robert Frisch experimentally confirms Otto Hahn and Fritz Strassman's discovery of nuclear fission. Frisch goes to Copenhagen to share the discovery with Niels Bohr, who in turn reports the discovery to his American colleagues. Bohr and John Archibald Wheeler determine later that year through chain-reaction experiments at Princeton University that uranium-235 could produce a nuclear explosion. • 1939 – April – Nazi Germany begins the German nuclear energy project. • 1939 – September 1 – World War II begins after the invasion and subsequent partition of Poland between Nazi Germany and the Soviet Union. • 1939 – October – U.S. President Franklin D. Roosevelt receives the Einstein–Szilárd letter and authorizes the creation of the Advisory Committee on Uranium. The Uranium Committee has its first meeting on October 21, and $6,000 was budgeted for conducting neutron experiments. == 1940–1950 ==

• 1940 – April – The MAUD Committee (Military Application of Uranium Detonation) is established by Henry Tizard and the British Ministry of Aircraft Production to investigate feasibility of an atomic bomb. • 1940 – May – The paper which Dr. Yoshio Nishina of Nuclear Research Laboratory of Riken and Professor of Chemical Institute, Faculty of Science, Imperial University of Tokyo, Kenjiro Kimura presented to Physical Review, showed that they had produced neptunium-237 by exposing triuranium octoxide to fast neutrons for more than 50 hours. • 1940 – May - After the defeat of Belgium in only 18 days, the Nazis took possession of a significant amount of high quality uranium ore from the Belgian Congo, some still "on the docks". In 1939 both Britain and France had expressed interest in securing Belgium's uranium inventory but no action was taken. • 1940 - June - The French Third Republic collapses during the Battle of France. The rapid military collapse would contribute to nearly universal French public support for a nuclear deterrent in later years. • 1940 – July – The paper explaining that Dr. Yoshio Nishina and Kenjiro Kimura discovered symmetric fission on the previously described test appeared in Nature. The LibreTexts libraries based upon work supported by the National Science Foundation says, "Multiple combinations of symmetric fission products are possible for fission chain reactions." And, again, it as fission product yield, is known that the higher the energy of the state that undergoes nuclear fission is more likely a symmetric fission. • 1940 – July – The Soviet Academy of Sciences starts a committee to investigate the development of a nuclear bomb. • 1940 – September – Belgian mining engineer Edgar Sengier orders that half of the uranium stock available from the Shinkolobwe mine in the Belgian Congo—about 1,050 tons—be secretly dispatched to New York by African Metals Corp., a commercial division of Union Minière. • 1942 – October - 100 tons of Sengier's uranium ore is sent to Canada for refining by Eldorado Mining and Refining in Port Hope, Ontario. • 1944 – September – The first plutonium reactor is activated in Hanford, but shuts itself off immediately. • 1945 – June – The Office of Military Government, United States hands over Nordhausen, including the Mittelwerk factory where the V-2 rocket was constructed, to the Group of Soviet Occupation Forces in Germany. Soviet forces find documents and equipment from the factory and recruit Helmut Gröttrup. • 1946 – June – First meeting of the United Nations Atomic Energy Commission, which was established by the first resolution of the U.N. General Assembly, is held. • 1946 – June – The Soviet Union rejects the Baruch Plan. • 1946 – August – The Convair B-36 Peacemaker is introduced as the first purpose-built nuclear bomber. • 1946 – December 25 – The Soviet Union activates the F-1 pile in Moscow, producing the first controlled nuclear reaction in Europe. • 1947 – The RTV-A-2 Hiroc, the first design of an intercontinental ballistic missile, is cancelled by the United States. • 1947 – A steppe near Semipalatinsk, Kazakh SSR is selected by Beria as the Soviet Union's nuclear test site. • 1947 – January – British prime minister Clement Attlee approves the development of an atomic bomb through the High Explosive Research programme led by William Penney, Baron Penney. • 1949 – August 29 – The Soviet Union conducts its first atomic test, RDS-1 (nicknamed Joe 1 by the Americans). ==1950–1960==

• 1950 - The US Air Force Strategic Air Command (SAC) stations 11 model 1561 Fat Man atomic bombs at RCAF Station Goose Bay in Labrador. • 1950 – January 31 – President Harry S. Truman authorizes the development of the hydrogen bomb. • 1950 – Klaus Fuchs and Julius and Ethel Rosenberg are arrested in the United States for leaking atomic secrets to the Soviet Union. • 1951 – January 12 – In response to the threat of a Soviet nuclear attack, President Truman creates the Federal Civil Defense Administration. The FCDA is succeeded by the Federal Civil Defense Authority in 1972, which is in turn succeeded by the Federal Emergency Management Agency in 1979. • 1951 – President Truman establishes the CONELRAD emergency broadcasting system to alert the United States to an enemy attack. The system is later succeeded by the Emergency Broadcast System in 1963 and the Emergency Alert System in 1997. • 1951 – The United States opens the Nevada Test Site for nuclear weapons tests. • 1951 – MacArthur, with the approval of the Commander-in-Chief of the Strategic Air Command Curtis LeMay and South Korean President Syngman Rhee, pressures the government for the use of nuclear weapons against China. He is overruled and it becomes a factor in President Truman's relief of General Douglas MacArthur. • 1954 – December 26 – The French nuclear weapons program is secretly established by Prime Minister Pierre Mendès France. • 1955 – January 15 – China begins Project-596 under Marshal Nie Rongzheng with the approval of Mao Zedong. The Third Ministry of Machine Building, a predecessor of the China National Nuclear Corporation, is created to oversee the project. • 1955 – February – The Boeing B-52 Stratofortress replaces the B-36 as the U.S. Air Force's primary strategic nuclear bomber. • 1955 – India purchases a PUREX reactor from Canada and the United States, and constructs the Bhabha Atomic Research Centre at Trombay. • 1955 – West Germany joins NATO, allowing it to participate in nuclear sharing. • 1955 – February – The President's Science Advisory Committee recommends that the United States make missile production a national priority. • 1956 – The nuclear-capable PGM-19 Jupiter medium-range ballistic missile is created from the Redstone rocket. • 1956 – October–November – The Soviet Union threatens nuclear strikes against the United Kingdom and France during the Suez Crisis. • 1956 – November 30 – France establishes a secret committee for the Military Applications of Atomic Energy under Pierre Guillaumat and Yves Rocard. It establishes a secret protocol between the CEA and the Ministry of Defence for procuring weapons material. • 1957 – July – The International Atomic Energy Agency is founded. • 1957 – August 26 – The Soviet Union announces the successful test of an intercontinental ballistic missile, the R-7 Semyorka, capable of flying "into any part of the world." • 1957 – October 4 – The Sputnik 1, the first artificial satellite, is launched using a modified version of the Soviet Union's ICBM, beginning the Space Race. • 1957 – In response to the new threat of Soviet ICBMs, the U.S. Army accelerates production on the Nike Zeus missile, an anti-ballistic missile designed to intercept ICBMs in mid-air. • 1957 – Operation Antler, the final British nuclear test in Australia, occurs in Maralinga, South Australia. • 1957 – October 10 – The Windscale fire occurs in Seascale, Cumbria after a graphite-moderated reactor built for the British hydrogen bomb project catches fire, resulting in the release of radioactive contamination across the United Kingdom and Europe. An inquiry determines that the accident was avoidable and that the British Army ignored warnings by scientists, but is suppressed by the government to prevent damaging the Special Relationship. • 1957 – October 15 – The Soviet Union agrees to provide a "sample bomb" and extensive technical assistance to the Chinese nuclear program. • 1957 – December 17 – The Strategic Rocket Forces is established to maintain the Soviet nuclear arsenal. • 1958 – The United States and the United Kingdom sign the 1958 US-UK Mutual Defence Agreement. This is a bilateral treaty on nuclear weapons cooperation signed after the United Kingdom successfully tested a hydrogen bomb during Operation Grapple. Under the agreement the United States supplies the United Kingdom with nuclear weapons through Project E. • 1958 – The U.S. Air Force drafts Project A119, a classified plan to detonate a nuclear bomb on the Moon. The plan is quickly cancelled in favor of a Moon landing. • 1958 – RAFAEL is formed by the Israeli Ministry of Defense to coordinate its nuclear program. • 1958 – The Jiuquan Atomic Energy Complex is opened in China in the Gansu Province. • 1958 – The United States considers a nuclear strike on China during the Second Taiwan Strait Crisis, in which China resumed its bombardment of Kinmen and the Matsu Islands. • 1958 – January – The United States deploys nuclear weapons to South Korea. • 1958 – August – The PGM-17 Thor intermediate-range ballistic missile, the U.S. Air Force's first ballistic missile, is declared operational and begins deployment in the United Kingdom through Project Emily. • 1958 – November 4 – The Democratic Party wins the 1958 United States elections in part due to public perception of a "missile gap" against the Soviet Union following the release of the Gaither Report. Although later proven to be an overestimate, the concept later helps John F. Kennedy to win the 1960 presidential election. • 1958 – November 10 – Soviet general secretary Nikita Khrushchev makes a speech demanding the withdrawal of American, British, and French forces from West Berlin, beginning a series of political crises. • 1959 – Nuclear tests in Antarctica are banned under the Antarctic Treaty. • 1959 – Fidel Castro takes power in Cuba and creates a Marxism–Leninist government aligned with the Soviet Union. • 1959 – The Soviet Union scales back nuclear assistance to China as a result of the emerging Sino-Soviet split. == 1960–1970 ==

• 1960 – The United Kingdom cancels the De Havilland Blue Streak medium-range ballistic missile in favor of the American-produced Douglas GAM-87 Skybolt air-launched ballistic missile, ending its attempts to produce an independent delivery system. • 1960 – RAND Corporation analyst Herman Kahn releases On Thermonuclear War, which argues that the destructiveness of nuclear war can be limited through anti-aircraft defenses, civil defense preparations, and a doctrine targeting counterforces. The book becomes influential in U.S. nuclear strategy and helps formulate the Kennedy administration's policy of flexible response. • 1960 – Operation Chrome Dome, in which nuclear-armed B-52 bombers are continually flown by the U.S. Air Force close to the Soviet Union on continuous alert, begins. • 1960 – February 13 – France successfully tests a nuclear weapon, called Gerboise Bleue, in the Sahara near Reggane, French Algeria. • 1960 – 1 May – An American Lockheed U-2 spy plane piloted by Francis Gary Powers is shot down over Soviet territory, deteriorating Soviet Union–United States relations, sabotaging the Four-Power summit in Paris, and hindering General Secretary Khrushchev's policy of peaceful coexistence. • 1960 – December – The China Institute of Atomic Energy begins research on thermonuclear weapons. • 1961 – The Israeli Prime Minister David Ben-Gurion informed the Canadian Prime Minister John Diefenbaker that a pilot plutonium-separation plant would be built at the Dimona reactor. Intelligence would indicate from this and other information that Israel intended to produce nuclear weapons. • 1961 – Australia considers purchasing nuclear weapons from the United Kingdom, but the idea is rejected by the Cabinet of Prime Minister Robert Menzies. • 1961 - President Kennedy announces that the federal government will begin the construction of fallout shelters. • 1961 – October 27 – The Berlin crisis occurring after the construction of the Berlin Wall by East German authorities culminates when the United States deploys tanks to Checkpoint Charlie, a move reciprocated by the Soviet Union. President Kennedy and General Secretary Khrushchev ultimately negotiate the removal of the tanks through diplomatic backchannels and prevent a war. • 1962 – December 21 – President John F. Kennedy and Prime Minister Harold Wilson ratify the Nassau Agreement agreeing for the United States to supply the United Kingdom with Polaris submarine-launched missiles. The Polaris Sales Agreement is signed on 6 April 1963 by Secretary of State Dean Rusk and British Ambassador to the United States David Ormsby-Gore. • 1963 – August – The Treaty Banning Nuclear Weapon Tests in the Atmosphere, in Outer Space and Under Water opens for signatures. The treaty limited nuclear weapons tests to underground detonations. • 1963 – August – President Kennedy considers using conventional and nuclear air strikes against China's nuclear facilities to prevent it from developing an atomic bomb. • 1963 – American nuclear weapons are deployed at Canadian Armed Forces bases in West Germany, through the NATO nuclear sharing program. Additional American nuclear weapons systems are deployed in Canada under U.S. control through NORAD. • 1964 – January 29 – The Stanley Kubrick film Dr. Strangelove or, How I Learned to Stop Worrying and Love the Bomb is released satirizing predominant nuclear strategy. • 1964 – October 13 – Leonid Brezhnev becomes General Secretary of the Soviet Union, and increases military expenditures. • 1966 – France withdraws from SHAPE and the NATO integrated command structure due to disputes over its nuclear weapons and does not rejoin until 2009. • 1966 – The United States' nuclear stockpile peaks at 31,149 warheads. • 1966 - China begins moving its nuclear facilities into the interior during its Third Five-Year Plan. • 1967 – January – The Outer Space Treaty prohibits nuclear tests in space. • 1967 - February 27 – The Treaty of Tlatelolco is signed in Mexico City, creating a nuclear-weapon-free zone in Latin America. • 1967 – June 17 – China successfully tests a hydrogen bomb. • 1967 – June 23–26 – President Johnson and Soviet premier Alexei Kosygin express a willingness to conduct arms-control negotiations at the Glassboro Summit Conference. • 1968 – July – The Nuclear Non-Proliferation Treaty opens for signatures. This treaty is intended to limit the spread of nuclear weapons. To date, 189 countries have signed the treaty, including the five permanent members of the UN Security Council. Only India, Israel, Pakistan, and North Korea have not signed the treaty (as sovereign states). • 1968 – With its ratification of the Nuclear Non-Proliferation Treaty, Sweden formally ends the nuclear weapons program it has run since 1945. • 1969 – The United Kingdom transfers its strategic nuclear warheads to its Polaris submarines away from the aging V-bomber fleet. • 1969 – October – President Richard Nixon, as part of his "madman theory" postulating that the Soviet Union would avoid aggressive acts if they feared an unpredictable response from the United States, and National Security Advisor Henry Kissinger approve Operation Giant Lance, an operation involving nuclear-armed B-52 bombers flying near the Soviet border to simulate an American nuclear attack. • 1969 – November – The Strategic Arms Limitation Talks commence in Helsinki, Finland. ==1970–1980==

• 1970 – The LGM-30 Minuteman III, the United States's current intercontinental-ballistic missile, is introduced. • 1970 – The Soviet Navy considers constructing a base for nuclear submarines in Cienfuegos, Cuba. • 1971 – March 31 – The United States deploys the UGM-73 Poseidon submarine-launched ballistic missile on James Madison-class submarines. • 1972 – May – Pakistani nuclear scientist Abdul Qadeer Khan is employed at a Urenco Group nuclear laboratory in Amsterdam and makes repeated visits to an enrichment plant in Almelo. • 1974 – South Africa secretly decides to pursue a capability for nuclear bombs, ostensibly for peaceful nuclear explosions. • 1974 – May – India tests its first nuclear device, "Smiling Buddha", at Pokhran using a core designed by Rajagopala Chidambaram. • 1974 – May – Pakistan's Project-706 is established under command of General Zahid Ali Akbar. • 1974 – November – A major breakthrough in the SALT II negotiations occurs at the Vladivostok Summit Meeting on Arms Control between General Secretary Leonid Brezhnev and President Gerald Ford. • 1975 – The number of American nuclear warheads deployed in the Atlantic Ocean peaks at 4,500. • 1975 - China deploys its first intercontinental ballistic missile, the Dong-Feng 4. • 1975 - Brazil purchases a nuclear reactor from West Germany, a move criticized by the United States and Mexico due to concerns that it will use the reactor to produce nuclear weapons. • 1975 – December – Khan returns to Pakistan with photographs and blueprints from his job. • 1977 – March – The Boeing E-3 Sentry is introduced as NATO's primary AWACS aircraft. • 1977 – July 13 – Somalia invades Ethiopia in the Ogaden War, and congressional support for SALT II in the United States weakens as a result of Soviet intervention in the war. • 1978 – France begins development of the Aérospatiale Air-Sol Moyenne Portée missile. • 1978 – South Africa develops highly enriched uranium at the Valindaba site near Pretoria. • 1979 – December 12 – NATO makes its Double-Track Decision responding to the Soviet Union's increased deployment of RSD-10 Pioneer intermediate-range ballistic missiles and Tupolev Tu-22M bombers by deploying increased numbers of medium-range and intermediate-range ballistic missiles, including Martin Marietta Pershing II missiles and GD BGM-109G Gryphon Ground Launched Cruise Missiles, in Western Europe while continuing to make the Warsaw Pact offers for negotiations. This results in increased east–west international tensions and domestic political controversy. • 1979 – December 25 – The Soviet invasion of Afghanistan begins, resulting in collapse of support for SALT II. == 1980–1990 ==

• 1980 – January 3 – President Carter withdraws SALT II from the Senate for formal ratification. • 1982 – June 12 – The largest anti-war demonstration in history occurs against nuclear weapons in Central Park in New York City during a UN disarmament conference. • 1983 – March 20 – President Reagan announces the Strategic Defense Initiative to defend against a Soviet nuclear attack. • 1983 – September 26 – A false alarm occurs in the Soviet Union when the Oko early-warning system malfunctions and erroneously reports an incoming American missile strike. The Soviet Air Defense Forces command officer at the Serpukhov-15 bunker, Lieutenant Colonel Stanislav Petrov, correctly deduces that the alarm was false and does not report it to his superiors, preventing a retaliatory strike. • 1983 – 2 November-11 November – The Soviet Union, which had been monitoring American nuclear forces through the KGB's Operation RYAN, mistakes NATO's Able Archer 83 command post exercise for genuine preparations for a preemptive nuclear strike, and places its forces in East Germany and Poland on high alert. • 1983 – November 20 – The television film The Day After premieres on ABC, significantly changing attitudes on nuclear war. A similar film, Threads, is released by the BBC and the Nine Network next year, while Testament is released by PBS and Paramount Pictures. • 1983 – December 23 – The United States begins its deployment of Pershing II missiles to West Germany. • 1984 – Canada no longer allows nuclear weapons to be stored in Canada. • 1985 – International Physicians for the Prevention of Nuclear War is awarded the Nobel Peace Prize. • 1985 – South Africa decides to covertly build nuclear weapons. • 1987 – Chang Hsien-yi, a colonel of the Republic of China Army and the deputy director of the INER, defects to the United States and provides the CIA with classified documents revealing a secret nuclear weapons program in Taiwan. The program is shut down by ROC president Chiang Ching-kuo under pressure from the IAEA and President Reagan. • 1987 – The United States ends production of nuclear material for weapons. • 1988 – Pakistan reportedly has the capacity to build a nuclear bomb. • 1989 – South Africa opts to dismantle the six nuclear weapons it has secretly built amid the negotiations to end apartheid. • 1989 – Communism collapses in the Eastern Bloc during the Revolutions of 1989. The Soviet Union and the United States subsequently hold the Malta Summit aboard the TS Maxim Gorkiy announcing the end of the Cold War. ==1990–2000==

• 1990 - July – NATO issues the London Declaration declaring its relations with the Warsaw Pact and the Soviet Union to be no longer adversarial and urging reductions in tactical nuclear forces in Europe. • 1990 – October 16 – The Radiation Exposure Compensation Act is ratified in the United States, providing monetary compensation to victims of radiation-related illnesses, including cancer, caused by contact with nuclear testing and uranium mining. • 1991 – South Africa signs the Nuclear Non-Proliferation Treaty; they also announce that from 1979 to 1989, they had built and then dismantled a number of nuclear weapons. The IAEA confirms that the program has been fully dismantled. • 1991 – France and China ratify the Nuclear Non-Proliferation Treaty. • 1992 – The U.S. Senate votes for a nuclear testing moratorium despite opposition from President George HW Bush and Defense Secretary Dick Cheney. Operation Julin is the final American weapons test, and also ends British nuclear testing in the United States. • 1992 – France's nuclear stockpile peaks at over 500 warheads. • 1993 – North Korea rejects IAEA inspections and threatens to withdraw from the Nuclear Non-Proliferation Treaty. • 1994 – January – The United States and Russia negotiate a detargeting agreement that they will no longer directly target each other with nuclear weapons. • 1994 – After a meeting between Kim Il-Sung and Jimmy Carter and the ratification of the Agreed Framework, North Korea agrees to freeze its nuclear program in exchange for aid, easing of sanctions, and two civilian light-water reactors, which are built by the Korean Peninsula Energy Development Corporation. • 1995 – April – Kazakhstan completes the transfer of its nuclear weapons to Russia. • 1996 – January – France performs its last nuclear tests to date on Moruroa atoll. • 1996 – April 11 – The Treaty of Pelindaba is ratified, creating a nuclear-weapon-free zone in Africa. • 1996 – July 29 – China conducts its final nuclear test. • 1997 – France launches Operation Xouthos, its final nuclear test. • 1997 – March 21 – France launches the first of its Triomphant-class submarines. • 1997 – After the U.S. Senate ratifies the START II Agreement, President Clinton and President Yeltsin begin negotiations for START III. The talks collapse due to tensions over NATO intervention in the Kosovo War, the 1998 U.S. bombing of Iraq, and Operation Infinite Reach. • 1998 – The United Kingdom decommissions the WE.177 bomb, the final warhead used by the Royal Air Force and the final tactical nuclear weapon used by Britain. The United Kingdom shifts towards exclusive reliance on its strategic SLBM programs for a nuclear deterrent in its Strategic Defence Review. • 1998 – May – India tests five more nuclear weapons as part of Operation Shakti at the Pokhran test site. This was India's second round of nuclear weapons testing. • 1998 – May – Pakistan detonates five high-enriched uranium nuclear weapons in the Chagai Hills. A sixth nuclear test, at Kharan, was a plutonium device. • 1998 – The Iraqi disarmament crisis intensifies after Saddam Hussein forces the UN inspectors out, leading to Operation Desert Fox. • 1999 – The U.S. Defense Intelligence Agency estimates that Israel possesses between 60 and 80 nuclear weapons. == 2000–2010 ==

• 2000 – January – Russia publicly begins to reformulate its doctrine to include the possibility of a nuclear response to a large-scale conventional attack. • 2006 – July – Prior to the 32nd G8 summit, Russia threatens to retaliate to missile defense preparations in Eastern Europe by targeting European urban centers. • 2008 – The Russian Navy conducts ten limited patrols with its strategic nuclear submarines, its greatest amount since the collapse of the Soviet Union. • 2008 – November – Poland and the Czech Republic agree to delay deployment of radar sites until after the 2008 United States presidential elections and the presidential transition. • 2009 – November 12 – President Obama announces changes to the NATO missile defense system, including an increased reliance on the sea-based Aegis Ballistic Missile Defense System and the AN/TPY-2 radar, and the RIM-161 Standard Missile 3 missile system. == 2010–present ==

• 2010 – North Korea reveals its new uranium-enrichment plant during tensions from the ROKS Cheonan sinking, the May 24 measures, and the bombardment of Yeonpyeong. • 2013 – The U.S. Department of Defense reports to Congress that the PLA Navy is developing a ballistic missile submarine force. • 2017 – July 7- The Treaty on the Prohibition of Nuclear Weapons, the first legally-binding international nuclear weapons ban, is ratified by 90 countries. The International Campaign to Abolish Nuclear Weapons wins the Nobel Peace Prize for its campaigning for the Treaty. • 2017 – September – North Korea conducted its seventh nuclear test with a yield between fifty and two hundred fifty kilotons, causing an international crisis. President Donald Trump adopts more bellicose rhetoric towards the country. • 2018 – March 15 – Crown Prince Mohammad bin Salman announces on a 60 Minutes interview that the Kingdom of Saudi Arabia will pursue nuclear weapons in the event of a successful Iranian nuclear test. • 2018 – April 27 – Kim Jong-un meets South Korean President Moon Jae-in in Panmunjom for a summit and pledges a denuclearized Korean Peninsula. • 2018 – May 1 – President Putin announces a major modernization to Russian nuclear forces in his annual Presidential Address to the Federal Assembly, including announcing the Avangard hypersonic glide vehicle. • 2018 – May 8 – President Trump announces the United States withdrawal from the Joint Comprehensive Plan of Action. • 2018 – June 12 – Trump and Kim meet at the 2018 North Korea–United States Singapore Summit, the first American and North Korean heads of state to meet, and issue a joint declaration pledging a denuclearized Korea. • 2019 – February – The United States and Russia withdraw from the INF Treaty. • 2019 – February 28 – The 2019 North Korea–United States Hanoi Summit ends prematurely without a deal, but both parties express commitment to a better relationship. ==See also==