Ukrainians say they're ready to fight for their country

KIEV, Ukraine - Ukraine is caught in the middle between the NATO countries, led by the United States, and Russia. East of the Dnieper River, most folks identify with Russia. To the west, most want to be part of Western Europe.

On Monday in Kiev's Independence Square -- the heart of the revolution -- there was a funeral for one of the leading figures of the protest movement that had forced Ukraine's pro-Russia President Viktor Yanukovych to flee.

"Heroes don't die," they chanted, and called him a patriot and a fighter.

Sergei Magdanik, an engineer, said he had heeded his government's call and joined the military. CBS News
Among the mourners was a 23-year-old engineer named Sergei Magdanik, who joined the demonstrations months ago. Now he's prepared for another fight: He has signed up with the Ukrainian army.

Is he worried about the possibility of fighting the Russians?

"Of course, we are worried, everybody's worried. But we cannot choose. It's our oath, our moral right," he said.

Russia sets ultimatums, tightens grip on Crimea
Ukraine's interim government has called on all men of fighting age to be ready to take up arms in case Russia makes another land grab in eastern Ukraine. Every man CBS News spoke to said they would.

The mood has changed here in Independence Square and throughout much of the country. Where they were celebrating the idea of a new future, they are mourning those who died for it. And they are worried about what comes next.

On Monday, acting Prime Minister Arseniy Yatsenyuk warned again that his government would never accept Russia's takeover of Crimea.

"For these actions, the price must be paid. No one will give Crimea back to anyone," Yatesenyuk said.

Obama urges diplomacy while examining punitive measures for Russia
But taking Crimea back would mean taking on the might of the massive Russian military. Does Magdanik believe the Ukrainian military and young men like himself are capable of defending their country against the Russians?

"We will do what we are capable of," said Magdanik said.

U.S. Secretary of State John Kerry's visit Tuesday is seen as a show of support for the new Ukrainian government, but it's unclear what he can do to find a diplomatic solution to the crisis, with no indication of either side backing down.