《朴茨茅斯条约》签订后,日本和俄国以长春为界平分了原俄国独霸的中东铁路及其附属地。自恃在日俄战争中调停有功的美国和日本的盟友英国都想趁机在中国东北推行门户开放政策,进一步拓展本国的商业和实业,却出乎意料地遭到了日本和俄国的联合抵制。然而,英美两国并不甘心就此退出,他们派出多支经济调查团和商业团体深入中国东北调研,在铁路、矿业、贸易等领域与日俄展开了多维度的竞争并最终取得了一定的成就。 After the Treaty of Portsmouth was signed, Japan and Russia divided Changchun into a Middle East railway and its ancillary places that used to dominate Russia. The United States and Japan’s ally, Britain, which have relied on their meritorious service in the Russo-Japanese War, all wanted to take the opportunity to promote the open door policy in northeast China and further expand their own businesses and industries. Unexpectedly, Japan and Russia had boycotted it. However, both Britain and the United States were not willing to withdraw from this. They dispatched more economic investigation teams and business groups to conduct in-depth investigations in northeast China and conducted multi-dimensional competition with Japan and Russia in the fields of railways, mining and trade and eventually achieved some successes .