From arms control to Afghanistan, analysts say the deals brokered by Obama and Medvedev could profoundly reshape global security.
Since President Obama took office, twice as many Russians report 'positive attitudes' toward the US. But skepticism continues to dominate ties between Washington and the Kremlin.
His administration isn't that interested in a missile shield in Europe, but seems unlikely to concede it in upcoming talks.
Although both countries claim the military exercises are simply for practice, some wonder if the old dispute is again flaring.
Yunus-Bek Yevkurov, the Kremlin-backed president of Ingushetia, is the fourth government official in the North Caucasus targeted this month.