 Ipapo akava mutungamiriri anoshanda weEuropean neEurasia Affairs kuNational Security Council. Muchinzvimbo ichocho aive nebasa rekugadzirira US kumusangano weIstanbul wa2004nhengo dzeNATO uye musangano wePrague muna 2002. Muna Chikunguru 2005, Volker akazove Mutevedzeri Wemubatsiri Wemunyori weHurumende weEuropean uye Eurasian Affairs, achishanda pachinzvimbo ichocho kusvika agadzwa United States Permanent Representative kuNATO muna Chikunguru 2008 neMutungamiri George W. Bush. Volker akashanda saMumiriri munzvimbo iyoyo kubva muna Chikunguru 2, 2008, kusvika Chivabvu 15, 2009. 