On the whole, however, the gains of the war had proved sufficient to
justify the calculations of Japan’s leaders, and to strengthen the
forces within Japan that were working toward expansion. In 1900 Japan
took part as an equal with the Western powers in quelling the famous
Boxer Uprising, in China, and shared in the returns from the Boxer
Indemnity which they later imposed as a punishment on the Chinese. The
fact that the British thought it worth while to sign an alliance with
Japan in 1902 was an additional testimony to her growing prestige.
Fortified by this alliance, and by strenuous efforts to build up her
military and naval forces, Japan emerged successfully from her clash
with Tsarist Russia in 1904-05.
The peace terms did not include the indemnity Japan coveted, largely
because she was too exhausted to continue the struggle. But still there
were substantial gains. Japan won a protectorate over Korea, which
she converted to full annexation in 1910. The Russian leasehold at
the tip of the Liaotung Peninsula was transferred to Japan, and also
the Russian railway lines in South Manchuria. Finally, Russia ceded
the southern half of Sakhalin Island to Japan, and granted important
fishing rights in northern Pacific waters to Japanese interests.
The Treaty of Portsmouth, which set forth these terms and in which
President Theodore Roosevelt mediated, established Japan as the rising
power in the Far East. In 1905, three weeks before the treaty was
signed, the Anglo-Japanese Alliance was extended for ten years, with
provisions sanctioning Japan’s paramount interests in Korea.