Large scale copper mining replaced saltpeter extraction as the country's main source of wealth.The Chilean copper mines were nationalized in the 1950's. In the Pinochet era they were transferred into the public company Codelco. Their revenue represent a large share of the Chilean government budget revenue about 20% in the 1980s. Oil mining is also another important mineral for the country.<span />
<span>What was President Roosevelt's main concern when he offered the Treaty of Portsmouth to end the Russo-Japanese War? to keep Japan from becoming too strong to keep the peace in the entire region to stop Russia from winning the war to help Korea stay free and autonomous