Russia has effectively taken control of Ukraine's Crimea peninsula without a shot fired in anger. Now a larger question looms: What is Russian President Vladimir Putin's ultimate goal in Ukraine?
Russia and pro-Russian groups in Ukraine are moving swiftly to consolidate their hold on Crimea. Ukraine's interim government acknowledges it has lost control of the region. The U.S. and Europe have imposed limited sanctions and are discussing more, but their leverage is limited.
Putin and Russia hold most of the cards, analysts say, and they offer three broad scenarios about how the current crisis could play out.
1. Russia Keeps Advancing. Russia has faced few repercussions so far for its intervention beyond international criticism and mild sanctions and this may tempt Moscow to go further.
Some ethnic Russians in eastern Ukraine say they want Moscow to intervene in their region. Ethnic Russians have staged demonstrations, and even taken over government buildings temporarily, but the Ukrainian government remains in control for now.
Would Russia consider taking action?
"We know Putin wants Crimea at the very least. I think he also wants parts of eastern Ukraine, but we don't know what he will do," said Sergii Leshchenko, deputy editor of Ukrainska Pravda, an online paper in Kiev. "Putin is playing hardball and he wants to restore as much of the Soviet Union as he can get away with."
However, Russian moves beyond Crimea would further escalate the crisis. It could provoke violence in Ukraine and prompt the international community to take stronger action than it has so far.
Also, it's important to remember that Crimea is a special case. It was part of Russia for centuries before Soviet leader Nikita Khrushchev gave it to Ukraine as a gift in 1954. It's geography as a peninsula also makes it a place apart.
Therefore, many analysts don't see Russia moving troops or making other blatant grabs in eastern Ukraine at this point, though they don't rule it out.
"While both Ukraine and the West would howl in protest, Western inaction at Putin's successful wresting of control of (disputed territory) from Georgia in 2008 and Crimea from Ukraine recently might well lead him to conclude that he can do this again with little cost," says Mark Katz of George Mason University, who writes frequently on Russia.
2. Russia Holds Crimea And Pressures Ukraine. This may be the most likely scenario, according to many analysts.
With each passing day, Russia and its allies in Crimea are reinforcing the peninsula's ties to Russia. Crimean lawmakers traveled to Russia and were warmly received by fellow legislators on Friday, a day after Crimea's parliament voted to align itself with Russia.
Despite opposition from Ukraine, a March 16 referendum is planned in Crimea so residents can choose if they want to become part of Russia. Crimean broadcasters are now showing Russian television stations. Flights from Crimea's main airport to the Ukrainian capital, Kiev, now depart from the international terminal, suggesting that the rest of Ukraine is now considered a foreign country.
The Russians could also play a disruptive role in Ukraine's national elections, set for May 25, to replace the government ousted last month by protesters in Kiev.
Russia's intervention in Crimea has turned many voters against pro-Russian candidates in Ukraine, according to Leshchenko, the Ukrainian journalist. But, he adds, "Russia doesn't want this election to take place at all and I think they are going to make a great effort to stop the entire process."
Russia also has the ability to put financial pressure on Ukraine, which is extremely vulnerable economically. Moscow is already saying it will increase the price of gas that it ships to its neighbor.
3. Russia Makes Limited Concessions. Putin and Russia have already gone too far to pull back to the positions in place before the current crisis, said Stephen Larrabee, who specializes in European Security at the Rand Corp.
"What's happened in Crimea is a fait accompli. You aren't going to get the Russians out of there," Larrabee said. "I can't see Putin agreeing to withdraw troops that are already there. It would be losing face with his own public."
In Putin's view, his ally in Ukraine, the former president Viktor Yanukovych, was ousted in a coup. In taking Crimea, Putin sees himself as standing up for Russia and ethnic Russians in former Soviet states.
Still, there may be limits to how far Putin will go. He believes Russia should be a major player in many parts of the globe, and if he finds himself isolated over Crimea, it may revise his calculations. In addition, sanctions and other punitive measures may have limited impact in the short term, but could bite over time.
"There is, it seems, little the West can do to evict the Russian troops," wrote Max Boot in Commentary magazine. "But there is much more that the West could be doing to make Russia pay a higher cost for its brazen aggression."
The U.S. Treasury Department could ban Russian financial institutions from interacting with U.S. banks, and force other countries to comply or face a similar ban, he wrote. That would be a major step and European banks would surely balk. But Russia is now part of the global economy and could be harmed by a concerted sanctions effort.
Greg Myre is the international editor for NPR.org. You can follow him on Twitter @gregmyre1