Dec 8. South Korea has announced the extension of its air defense zone (to take effect Dec. 15). The new zone overlaps the zones claimed by Japan and China.
In the East China Sea a dispute arose Nov. 23 when China announced new borders for its air defense zone, and warned that all aircraft entering this space must notify the Chinese authorities in advance, and that China's air force would be on high alert to firmly protect its airspace.
This warning was directed particularly at Japan, who has held an air zone which is overlapped by China's recent claim. This zone was decided by the victors of WWII, and is protected by America through the Japanese-American Treaty of Mutual Protection. The new Chinese zone also claims a submerged rock and research station belonging to South Korea.
The Senkaku Islands were annexed by Japan in 1895, before which no country had pronounced any claim over them. America occupied them for a period after the 1945 Japanese surrender. The islands have been used for ecological surveys and US military bombing sites since the 1940's, when the last residents stopped fishing there. The islands were privately owned by Japanese entrepreneurs since 1900 and rented by the Japanese government until 2012 when the Japanese government bought the islands.
Taiwan and China have claimed the islands since 1971. China and Taiwan claim ownership from 1534 and claim that the islands, though signed over to Japan in the first Sino-Japanese war, should return to China because after WWII Japan released certain of its territories. Japan rejects both claims.
No details specific to these islands are contained in the treaties wherein Japan gained or ceded control of her empire. What is stated in both the 1895 and the 1951 treaties is that Japan gains and then relinquishes Formosa and "all islands appertaining to or belong to Formosa."
America administered the area from WWII to 1972, when it returned ownership to Japan. The US does not have an official position on the competing claims. However, the Treaty of Mutual Cooperation and Security between the US and Japan binds America to protect these islands (confirmed by US government officials 2004, 2010, and 2012, when the US senate amended the National Defense act for 2013 to specifically cover the Senkakus as protected Japanese territory). The US government has also mentioned the Senkakus specifically since the discovery of nearby oil reserves in 1969 and since the Taiwanese and Chinese contentions in 1971. Before that time, the Senkakus were not mentioned; only the Ryukyu island chain was mentioned as Japanese territory.
Recent years have seen protests and clashes between Chinese and Japanese boats and in some cases air craft.
Nov. 23 after announcing their claim, China sent an air force mission to patrol the area. Japanese commercial flights were ordered to disregard the Chinese warnings. Nov. 26 America, who declared the airspace international, flew two unarmed B-52s through it. The US military stated that they would continue to do so and without identifying themselves. South Korea and Japan have also sent military aircraft to the area. Commercial airlines have been using the area uninterruptedly since China's warnings. America, Japan, and South Korea have protested China's statement claiming new airspace.
South Korea possesses the submerged rock called Ieodo, upon which rests a South Korean research station. The rock is also claimed by China. The South Korean air defense zone was established by the US during the Korean War. The US, Japan and China have agreed that the expansion of the South Korean air zone is in line with international law.
Many commentators note the importance of the islands as oil and gas reserves. In 2009 the US sanctioned Iranian oil and gas. Japan had been importing oil from Iran until then (so had China, which bypassed US sanctions). Some commentators point to the economic gains that come from military expansion as a motivation for increasing tensions in the area.
1939 the project to develop nuclear bombs, the "Manhattan Project," led by the US, supported by the UK and Canada (but not informing the other Ally Russia), taking place at 30 sites over the three countries, while gathering information on the German nuclear project and gathering German nuclear materials and scientists (and many other European exiles). The main priority was to produce fission-based explosives before Germany. It was the largest industrial enterprise ever at the time.

1945 July 16 America detonated a bomb code-named "Trinity". Truman, receiving news of the success, briefed Churchill and informed Stalin that America was in possession of a "powerful new weapon," which was no surprise to Stalin, who had spies in the Manhattan Project. July 26 an ultimatum was issued that Japan surrender or face "complete and utter destruction." 1945 Aug. 6 Truman gave permission for the world's first use of an atomic weapon on Hiroshima and on the 9th Nagasaki. After Hiroshima, Truman announced,

"We are now prepared to obliterate more rapidly and completely every productive enterprise the Japanese have above ground in any city. We shall destroy their docks, their factories, and their communications. Let there be no mistake; we shall completely destroy Japan's power to make war. It was to spare the Japanese people from utter destruction that the ultimatum of July 26 was issued at Potsdam. Their leaders promptly rejected that ultimatum. If they do not now accept our terms they may expect a rain of ruin from the air, the like of which has never been seen on this earth ..."
Aug. 9 Early morning word reached Tokyo that the Neutrality Pact with the USSR was over, as Moscow declared war on Japan and invaded Manchuria. Before noon Tokyo received word that Nagasaki had been bombed. After a day of debate over the terms of surrender, after midnight that night the Emperor is remembered to have stated,
"I have given serious thought to the situation prevailing at home and abroad and have concluded that continuing the war can only mean destruction for the nation and prolongation of bloodshed and cruelty in the world. I cannot bear to see my innocent people suffer any longer. ..."
It goes without saying that it is unbearable for me to see the brave and loyal fighting men of Japan disarmed. It is equally unbearable that others who have rendered me devoted service should now be punished as instigators of the war. Nevertheless, the time has come to bear the unbearable. ...
I swallow my tears and give my sanction to the proposal to accept the Allied proclamation on the basis outlined by the Foreign Minister."
The Privy Council Secretary was remembered to have asked, "Your majesty, you also bear responsibility for this defeat. What apology are you going to make to the heroic spirits of the imperial founder of your house and your other imperial ancestors?"
Aug 10 early the Foreign Ministry sent telegrams by way of the Swiss Federal Political Department announcing the acceptance of the Potsdam conditions of surrender, reserving only the prestige and rights of the Emperor. After more conventional bombing flights over Japan, the Emperor and his cabinet transmitted to their embassies in Switzerland and Sweden their notice of surrender on Allied terms
1946 Congress established the American Energy Commission and transferred control of nuclear projects from the military.
1949 Aug. 29 USSR detonated a bomb, the "Joe-1". Volunteer spies in the Manhattan Project had been informing Moscow of the progress of that project. The Russians put their full efforts into their own atomic project. America had monopolized the best uranium reserves (in Belgian Congo). The first Soviet test surprised America, who predicted the Soviets would realize their bomb years later. The test was reported to the world by Truman, when the Americans detected the fallout in Kazakhstan with the test-detection system they had secretly built on their WB-29 Superfortress. The arms race and domestic persecution of political enemies increased and in 1950 Truman announced a speedy program to design a more powerful bomb, the hydrogen bomb (tested Nov. 1952, announced Jan. 1953, matched by the Soviet's Aug. 1953). 1951 China agreed to supply the USSR with uranium in exchange for nuclear technology (an agreement which faltered when the two countries started to fall out after Stalin's death).
1950 Apr. 10 Britain detonated a bomb.
1960 Feb. 13 France detonated a bomb, Berboise Bleue, in the middle of the Algerian Sahara Desert.
1964 Oct. 16 China detonated a bomb.
1967 (or thereby) Israel is believed to have possessed nuclear capability.
1974 May 18 India detonated a bomb.
1979 (possibly that date) South Africa detonated a bomb.
1998 May 28 Pakistan detonated a bomb.
2006 Oct. 9 North Korea detonated a bomb.