Development of the Policy

In the 1890s, the United States had become an East Asian power through the acquisition of the Philippine Islands, and when the partition of China by the European powers and Japan seemed imminent, the U.S. government strove to preserve equal industrial and commercial privileges. Secretary of State John Hay sent (1899) notes to the major powers (France, Germany, Great Britain, Italy, Japan, and Russia), asking them to declare formally that they would uphold Chinese territorial and administrative integrity and would not interfere with the free use of the treaty ports within their spheres of influence in China. In replying, each nation evaded Hay's request, taking the position that it could not commit itself until the other nations had complied. However, in Mar., 1900, Hay announced that the powers had granted consent to his request. Only Japan challenged this declaration, and the Open Door became an international policy. After the Boxer Uprising, Hay dispatched (1900) a similar circular note.

Violations and the End of the Policy

Two years later, the U.S. government protested that Russian encroachment in Manchuria was a violation of the Open Door. When Japanese replaced Russian influence in S Manchuria after the Russo-Japanese War (1904-5) the Japanese and U.S. governments pledged to maintain a policy of equality in Manchuria. In finance, American efforts to preserve the Open Door led (1909) to the formation of an international banking consortium through which all Chinese railroad loans would be made. The United States withdrew in 1913, asserting that the consortium violated Chinese administrative integrity.

The next violation of the Open Door policy occurred in 1915, when Japan presented to China the Twenty-one Demands. That incident led (1917) to another exchange of notes between the United States and Japan in which there were renewed assurances that the Open Door would be respected, but that the United States recognized Japan's special interests in China. The Open Door principle had been further weakened by a series of secret treaties (1917) between Japan and the Allies, which promised Japan the German possessions in China.

The increasing disregard of the Open Door was a main reason for the convocation of the Conference on the Limitation of Armament (1921-22) in Washington, D.C. As a result of the conference, the Nine-Power Treaty, guaranteeing the integrity and independence of China and reaffirming the Open Door principle, was signed by the United States, Great Britain, Japan, France, Italy, the Netherlands, Portugal, China, and Belgium. With the Japanese seizure (1931) of Manchuria and the creation of Manchukuo, however, the Open Door received its greatest reverse.

After World War II, China's position as a sovereign state was recognized. No nation, therefore, had the right or capacity to carve out spheres of influence or to attempt to exclude other states from trade, and the Open Door policy ceased to exist.

Movable barrier installed in the entry of a room or building to restrict access or provide visual privacy. Early doors were hides or textiles. With monumental architecture came pivoting doors of rigid, permanent materials; important chambers often had stone or bronze doors. Pompeiian doors looked much like modern wooden doors; they were constructed of stiles (vertical planks) and rails (horizontal planks) fastened together to support panels and occasionally equipped with locks and hinges. The typical Western medieval door was of vertical planks backed with horizontal or diagonal bracing. In the 20th century, a single, hollow-core panel door became most common. Other types include the revolving door, folding door, sliding door (inspired by the Japanese shoji), rolling door, and Dutch door (divided horizontally so that the lower or upper part can be opened separately).

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Peninsula, northeastern Wisconsin, U.S. Located between Green Bay and Lake Michigan, it was named for a strait at its tip known as La Porte des Mortes (“Death's Door”). About 80 mi (130 km) long and 25 mi (40 km) wide at its base, the peninsula was visited in the 17th century by French traders and missionaries. It is now a year-round vacation area, and tourism is a major business. The whole peninsula is popularly known as Door County, though Door is but one of four counties on the peninsula.

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