Newly established in the Philippines and firmly entrenched in Hawaii at the turn of the century, the United States had high hopes for a vigorous trade with China.  However, Japan and various European nations had acquired established spheres of influence there in the form of naval bases, leased territories, monopolistic trade rights, and exclusive concessions for investing in railway construction and mining.

Idealism in American foreign policy existed alongside the desire to compete with Europe's imperial powers in the Far East.  The U.S. government thus insisted as a matter of principle upon equality of commercial privileges for all nations.  In September 1899, Secretary of State John Hay advocated an "Open Door" for all nations in China – that is, equality of trading opportunities (including equal tariffs, harbor duties, and railway rates) in the areas Europeans controlled. Despite its idealistic component, the Open Door, in essence, was a diplomatic maneuver that sought the advantages of colonialism while avoiding the stigma of its frank practice.  It had limited success.

With the Boxer Rebellion of 1900, the Chinese struck out against foreigners. In June, insurgents seized Beijing and attacked the foreign legations there. Hay promptly announced to the European powers and Japan that the United States would oppose any disturbance of Chinese territorial or administrative rights and restated the Open Door policy. Once the rebellion was quelled, Hay protected China from crushing indemnities.  Primarily for the sake of American good will, Great Britain, Germany, and lesser colonial powers formally affirmed the Open Door policy and Chinese independence.  In practice, they consolidated their privileged positions in the country.

A few years later, President Theodore Roosevelt mediated the deadlocked Russo-Japanese War of 1904-05, in many respects a struggle for power and influence in the northern Chinese province of Manchuria.  Roosevelt hoped the settlement would provide open-door opportunities for American business, but the former enemies and other imperial powers succeeded in shutting the Americans out.  Here as elsewhere, the United States was unwilling to deploy military force in the service of economic imperialism.  The president could at least content himself with the award of the Nobel Peace Prize (1906).  Despite gains for Japan, moreover, U.S. relations with the proud and newly assertive island nation would be intermittently difficult through the early decades of the 20th century.