By the thousands, protesters marched to Michigan Avenue, demanding the United States and the North Atlantic Treaty Organization do more to defend Ukraine.

“We need to close the skies above Ukraine,” said Ukrainian Congress Committee of America member Dan Diaczun.

Ukrainian Americans called for a no-fly zone to protect civilians from Russian air campaigns.

“NATO was formed for the very reasons we should protect Ukraine, every inch of Ukraine,” Congressman Mike Quigley.

Dozens who marched Sunday demonstrated the devastating impact of Russian bombs.

Ukrainian American veteran Gene Kinal said the ongoing attacks are “like a living nightmare.”

“I don’t understand how this can be happening in the 21st century in a humane world.”

Others showed their Ukrainian pride in the most prominent display possible. Ukrainian American veterans hoisted the 30-foot-by-60-foot flag over the Kennedy Expressway.

“You just feel helpless,” Ukrainian American Myron Weres said. “You want to do so much to help them but all we can do is this stuff, you know?”

The Ukrainian Cultural Center has collected more than 14,000 pounds of donations – non-perishable food, clothes and medical supplies.

“Shipping it off to Poland and then from there it’s going to people in need to Ukraine,” said native Iryna Panchuk. “It’s just really wonderful to see people as passionate about the issue as you are even though they might not have the same connection to it.”

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But Ukrainians say what they want most is the US and NATO to stand by them as they fight for freedom.

“We’re pretending that sanctions are going to work, we’re pretending that diplomacy is going to work,” Kinal said. “But mark my words, Putin is not going to stop at Ukraine.”

The US has said that a no-fly zone isn’t an option because it could bring the US into direct conflict with Russia. Amid Sunday’s rally, one of the organizers announced he’s calling for a boycott of American companies still operating in Russia – including Chicago-based McDonalds.