As Air Force One landed in Estonia's capital Wednesday, President Barack Obama's message to Vladimir Putin -- only 500 miles away in Moscow -- was clear: Stay put. Obama's trip to the former Soviet state, ahead of this week's NATO summit in Wales, is meant to reassure nervous Eastern Europe that Putin's support for separatists in Ukraine doesn't mean he has a free pass for territorial gains elsewhere. In a speech in Tallinn, Obama said the vision of a Europe dedicated to peace and freedom is "threatened by Russia's aggression against Ukraine," but said NATO will not allow that aggression to go unchecked.
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"We will defend our NATO allies," President Barack Obama says
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Peaceful Europe "threatened by Russia's aggression against Ukraine," Obama says
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Militant Islamists' gains in Iraq and Syria also cause for concern for NATO members
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Summit originally scheduled to address Afghanistan's future when troops leave
Russian official: @placeholder is emotionally in Ukraine, its troops are not