The document discusses the geopolitical importance of oil reserves in the Caspian Sea region and the role this played in US and other countries' foreign policy decisions. It suggests that the US invasion of Afghanistan and support for certain regimes in the region were motivated partly by desires to secure oil and gas pipelines from the Caspian to international markets. However, US officials publicly denied that oil was a factor and emphasized other stated rationales like national security and counterterrorism. The control of Caspian energy resources was an area of competition and strategic interest for major powers like the US, Russia, and China.