Where will Putin stop? As Ukraine holds on, Eastern Europe holds its breath

If his campaign succeeds in Ukraine, Putin could turn his attention to Moldova or Georgia, two former Soviet republics that today have breakaway regions occupied by Russian troops, said Karin von Hippel, a nonpolitical senior adviser at the State Department during the Obama administration. Neither Moldova nor Georgia are NATO members. But if Putin "starts to slowly expand his empire, there will be several other places that are in NATO that are going to be getting extremely stressed out," said von Hippel, who is now the director-general of the Royal United Services Institute in London.