Although the Cold War rivalry with Moscow has never been forgotten, current and former Western officials say Russia's annexation of Crimea has NATO powers tearing up strategic assumptions and grimly considering both conventional and nuclear fights.
As late as March, most NATO powers – with the exception of eastern members such as the Baltic States long worried by Moscow – had assumed Europe itself faced no imminent military threat. Full story
_Caption: U.S. soldiers walk after a ceremony for the arrival of the first company-sized contingent of about 150 U.S. paratroopers from the U.S. Army's 173rd Infantry Brigade Combat Team based in Italy in Swidwin, northern west Poland April 23, 2014. REUTERS/Kacper Pempel _