Question

What was one cause of the Russo-Japanese War?

Russia launched a secret attack on Japanese warships at Port Arthur.
Russia and Japan were competing for dominance in Korea and Manchuria.
Japan was angered by the Treaty of Portsmouth between Russia and the US.
Russia and Japan clashed over Russian military forces in the Japanese capital.

Answer 1

to calm tensions created by the segregation of Japanese students in California

Step-by-step explanation:

Answer 2

The main cause of the Russo-Japanese War was the territorial claims both countries made on Manchuria (an area partly in Russia and partly in China) and the Empire of Korea. ... The Russians had concluded a treaty with China for this in 1896 so that they could enter Chinese Manchuria without problems.

Step-by-step explanation:

Although tensions in the region were far from over, the Russo-Japanese War did shift the balance of global power, marking the first time in modern history that an Asian nation had defeated a European one in military combat. It would also mark the beginning of warfare involving world powers in the Pacific region.