US
Sunday also marks exactly four years since Putin signed a treaty declaring Crimea part of Russia
Putin sought to use election run-up to emphasise Russia's role as a major world power
President Putin’s grip today on Russia is stronger than ever
War of words between Moscow and London over poisoning of a former Russian spy escalates
World leaders who have held power the longest -- excluding monarchs enthroned for life
Extending Mr Xi’s tenure will ensure some measure of predictability in one way at least
America cannot allow nonproliferation efforts to fall, given tensions over nuclear programs in other countries
Putin unveiled the new Russian nuclear arsenal earlier in a state of the nation address
US Missile Defense Agency says hypersonic weapons create a 'significant' gap in US missile interceptor capabilities
Trump has accused Russia of helping North Korea evade international sanctions meant to punish Pyongyang