Vice President Joe Biden is traveling to Kiev Monday as the standoff between Ukraine and Russia continues to simmer.
His visit follows a weekend shootout at an eastern Ukraine checkpoint manned by pro-Russian insurgents that left at least three people dead.
Meanwhile, some observers fear Russian President Vladimir Putin has a long-range plan to revive at least part of the old Soviet Union.
Having already invaded and retaken South Ossetia from Georgia a few years ago and now Crimea from Ukraine, Russian troops are poised on the border of Ukraine, ready to take more.
"Russia, for once, is not on the defensive, it is advancing. That means it doesn't have to get flustered and can keep ploughing its furrow," Fyodor Lukyanov, editor of Russia in Global Affairs, warned.
The situation clearly has Ukraine's Prime Minister Arseniy Yatsenyuk worried.
"President Putin has a dream to restore the Soviet Union and every day he goes further and further and God knows where is the final destination," Yatsenyuk told NBC's "Meet the Press," Sunday.
But Putin's military ambitions carry a steep cost for Russia. The country is already getting hammered by a sudden credit crunch and capital flight.
A reported $51 billion has left Russia so far, and Russian companies have been shut out of global capital markets almost completely, meaning they'll need state money to stay in business.
But American lawmakers say Moscow needs to feel more economic pain.
"I think the time is now to rapidly ratchet up our sanctions whether it's on Russian petrochemical companies or on Russia banks," Sen. Chris Murphy, D-Conn., told NBC's "Meet the Press."
"If Russia does get away with this, I do think that there is a potential that a NATO ally is next," he warned. "And yes, there will be economic pain for Europe, but it's time for them to lead as well."
Many are at risk from a revived Russia, including Jews.
Anti-Semitic leaflets posted in the Ukrainian city of Donetsk calling for the registration of Jews with the authorities were reminiscent of Nazi-era persecution.
The Russia supporters said to be behind the leaflets denounced them as fake. Nevertheless, Jews are understandably upset.
"I can say that we are very shocked, shocked by the fact that someone allowed themselves to print and distribute such leaflets," Donetsk Rabbi Pinkhas Vyshedsky said.
Putin has said the greatest tragedy of the 20th century was the death of the Soviet Union. But many of Russia's neighbors clearly feel that the great tragedy of this century would be if Putin succeeds in reviving it.