Russia cannot be ignored. Since the end of the Cold War, Russia has never posed such a vexing problem to U.S. policymakers as it does now. [...] the Obama administration has been forced to accept that working with Russia is probably the only way to achieve results on many complicated international issues. [...] Russia was central in the Iran nuclear negotiations and is a player as well as negotiator in the Syria truce effort. [...] one of Hillary Clinton's first initiatives as secretary of state in 2009 was to "reset" relations with Moscow, an effort that produced decidedly mixed results.