afghanistan aksai chin al-qaeda alexander the great alfred thayer mahan baku-tbilisi-ceyhan pipeline caspian sea caucasus central asia chechnya china eurasia europe farkhor air base first anglo-afghan war first chechen war geostrategy great britain great power heartland hellenistic civilization hindu kush hinduism history of central asia history of china india indus river iran islam kashmir khunjerab pass khyber pass kyrgyzstan mohammed omar mongols nato nabucco pipeline new great game osama bin laden pakistan persian empire petroleum politics pipeline transport poland population qing dynasty russia second chechen war south caucasus pipeline steppe strategic geography tajikistan taliban the geographical pivot of history the great game tibet torugart pass turkestan turkey turkmenistan united states uzbekistan wakhan corridor xinjiang zbigniew brzezinski