Russia continued bombing civilian targets Wednesday in Ukraine's capital of Kyiv, while Ukrainian officials in the besieged city of Mariupol to the south said a Russian airstrike destroyed a theater which was serving as a shelter for hundreds of people whose homes were destroyed.
Russian forces also reportedly are holding hundreds of civilians hostage at a nearby hospital, with doctors treating injured and dying children.
Satellite photos did appear to show a Ukrainian strike at a Russian-held airport might have destroyed several Russian helicopters and vehicles.
President Zelenskyy spoke to Congress Wednesday and called for more help.
President Biden made a pledge of $800 million dollars with a long list of specific military aid that includes 800 Stinger anti-aircraft systems, 9,000 anti-armor systems including Javelins, 100 drones, as well as grenades, firearms and body armor.
President Biden also escalated his rhetoric with a new label for Russian President Putin.
"I think he is a war criminal," President Biden told reporters Wednesday.
"There's no argument with the bombings...it's about terrorizing the Ukrainian population and that is the war crime," said Stanford Professor Norman Naimark, an expert on Eastern European History.
Naimark says while Putin seems to have forced Zelenskyy to back away from joining NATO, Naimark says Putin also sees a democratic Ukraine as an ideological and economic threat.
"There are many different reasons why Putin went into Ukraine and clearly part of the context for going in was his annoyance at NATO expansion. But I think much more important was the danger that a democratic, solid, sovereign Ukraine would pose to his rule in Russia. I mean, he felt that if Ukraine could guide its own affairs could deal with its foreign policy on its own, that it would develop increasingly into a Western-style country, a successful democracy...that maybe it would join the European Union," said Naimark.
"It started with the idea that the Ukrainians wanted to be part of Europe. This was not a military alliance," said Naimark, "At that point it was fairly clear that they couldn't join NATO, but they were interested in was European Union. And the reason they were interested in the European Union is because the EU had been very helpful to other countries, you know, Poland, Hungary, Romania, Bulgaria and others to develop a functioning democracy, ridding the countries of corruption as best they could. So Ukraine was looking for kind of help from Europe to become a more perfect democracy."
"Initially, the then-president of Ukraine, a man named (Viktor) Yanukovich said, yeah, we'll do that. And then he went back on it with Putin's influence and pushing. He went back on and then that started the whole Revolution of Dignity," said Naimark, referring to what is also known as the Maidan Revolution of February 2014.
"The idea was to join Europe, we don't want to be part of the Moscow's world and the way you know, the Russians want to want us to be, and they eventually got rid of Yanukovych had some free elections," said Naimark, "So this was initially not about NATO at all, but about Europe. And I think this is just a kind of excuse, in some ways on the part of Putin for the invasion. It's an argument that he makes to himself and to the leadership in Russia and to his people. But in a lot of ways, I think it's a false argument."
Naimark says Putin's speech on Wednesday raises another concern about the flow of information and authoritarianism within Russia.
"Putin essentially today threatened what he called scumbags. He used terrible words for people who opposed the war. Essentially he's calling for a purge. It's like the Stalinist '30's," said Naimark.
Anastassia Fedyk, a Ukrainian-born professor of Economics at UC Berkeley wrote a piece for the Washington Post saying economic sanctions are good but not enough to stop Putin.
She says NATO countries should not underestimate the resolve of the Russian people to endure economic hardship if they feel that their country is under threat, a message which Putin is emphasizing in state propaganda, while silencing the Russian opposition press.
"My major fear is humanitarian cost and further escalation," said Fedyk.
Fedyk says she and other Ukrainian economists and professors are trying to help people in Ukraine with funding and logistical support from overseas, but Ukraine needs more help from NATO.
"It's just not that realistic for a country of 45-million to single-handedly defend European freedom," said Fedyk.
Jana Katsuyama is a reporter for KTVU. Email Jana at firstname.lastname@example.org and follow her on Twitter @JanaKTVU or Facebook @NewsJana or ktvu.com.