GEOFF BENNETT: Welcome to the "NewsHour."

Today is the one year is the first anniversary of Russia's full-scale invasion of Ukraine.

It is the largest war in Europe in 80 years, marked by calamitous destruction and death, but also by bravery and the resilient will of the Ukrainians.

AMNA NAWAZ: The somber day was observed around the world, at the United Nations, across Europe and most profoundly in Ukraine.

In Kyiv, President Volodymyr Zelenskyy spoke at length to the world media today, at times welling up with tears for his family and his country.

With the support of the Pulitzer Center, Nick Schifrin reports again tonight from Ukraine.

NICK SCHIFRIN: In the ancient heart of city that has endured one year of war, they sang the national anthem.

It is titled "Ukraine Has Not Yet Perished," a dark, but determined call to stay resilient on a solemn anniversary.

President Volodymyr Zelenskyy, his leadership forged in the fire of war, honored the men and women who have saved the country.

VOLODYMYR ZELENSKYY, Ukrainian President (through translator): I am grateful to everyone who endured last February, this past year, and who gives Ukraine invincibility.

NICK SCHIFRIN: There was a moment of silence for lives lost.

Zelenskyy honored grieving widows, and he awarded Ukrainian servicemen with the highest of awards, Hero of Ukraine.

And from a Kyiv basement, Zelenskyy gave a two-and-a-half-hour press conference and recalled for him what was the war's worst moment, the day he visited the sites of some of the war's worst atrocities.

VOLODYMYR ZELENSKYY (through translator): Bucha.

I think Bucha.

What I saw the moment we de-occupied Bucha, it was horrible.

What we have seen, the devil is not somewhere below us.

He is among us.

NICK SCHIFRIN: Two days after China's top diplomat visited the Kremlin, today, Beijing released a peace plan that called for respect for territorial integrity, but didn't detail what that meant.

Zelenskyy said today he would oppose the plan if it didn't call for a Russian withdrawal.

VOLODYMYR ZELENSKYY (through translator): As far as I know, China has historically respected territorial integrity, and so it should do everything so that the Russian Federation leaves our territory, as it is in this that the gravity of sovereignty and territorial integrity lies.

ANTONY BLINKEN, U.S. Secretary of State: No one wants peace more than the Ukrainian people.

NICK SCHIFRIN: At the U.N. Security Council, Secretary of State Antony Blinken advocated for what the U.S. and Ukraine call a just and durable peace.

ANTONY BLINKEN: For peace to be durable, it must ensure that Russia can't simply rest, rearm, and relaunch the war in a few months or a few years.

NICK SCHIFRIN: Today, the U.S. and other leaders of the seventh largest industrial nations announced new sanctions and export controls on Russia.

The U.S. also unveiled an additional $2 billion worth of military aid, including more ammunition for long-range rockets.

And, on this anniversary, much of the Western world showed solidarity, from Amsterdam, to Sydney, and even in Moscow, memorials on monuments devoted to Ukrainian writers.

But even those flower-bearers were quickly detained.

It is still illegal in Russia to call the war a war.

And a year is a long time to be at war, even for hardened warriors.

VOLODYMYR ZELENSKYY (through translator): My children are the most important people for me.

I do not see them often.

My parents, I do not see them at all.

I'm very proud of my wife.

NICK SCHIFRIN: That was Zelenskyy at his most vulnerable.

But he was also today at his most determined.

He ruled out any idea of negotiating with Vladimir Putin and said that the only vision for the end of this war that he could see is Russia's total withdrawal -- Amna, Geoff.

AMNA NAWAZ: Nick Schifrin with another tremendous piece of reporting there.

Nick, we just heard a little bit of what President Zelenskyy had to say today.

That was a two-hour press conference, as you know.

You were there.

What else stood out to you from his remarks?

NICK SCHIFRIN: Zelenskyy's spokesman called on more than 40 reporters across five continents.

There was clearly a desire from his team to get into the markets across from Latin America all the way to East Asia.

On the U.S., he was asked about Americans who are saying to pollsters that they believe the administration is spending too much money to support Ukraine.

And he warned that, if the U.S. did not support Ukraine enough to win over Russia, that Russia would eventually launch a war against NATO, and American soldiers would have to go and fight and die, like Ukrainian soldiers would fight and die, are fighting and dying right now.

And, on China, beyond the peace plan, he said that Beijing must not send weapons to Russia.

He said that was his -- quote -- "number one priority.

I'm doing everything I can to ensure that doesn't happen."

That, of course, is something that the U.S. is also warning Beijing is considering.

GEOFF BENNETT: So, Nick, you have been in Ukraine for the past two weeks.

This is your fourth reporting trip to that country since Russia launched its full-scale invasion last year.

You have interviewed Ukrainian troops.

You have spoken to everyday Ukrainians.

Is there a message that the people you have spoken with want to convey to Americans?

NICK SCHIFRIN: The message is two words: weapons and resilience.

Ukraine needs more weapons in order to launch a counteroffensive in the coming weeks and months.

And that's not only the armored vehicles that the U.S. is sending to try and launch that counteroffensive.

It's also basic ammunition.

I visited multiple units on the front, Geoff, that have said that they are short on ammunition.

And also resilience.

You hear that from Zelenskyy, to the soldier on the front, to the man who has just lost his home in Eastern Ukraine to a Russian rocket.

They are resilient in spite of, but because of all of the horrors, all of the crimes, what the U.S. calls crimes against humanity that I have been reporting on committed by Russian forces who are waging total war.

The person who pushed the button that launched the missile that struck 13 Marat Street, Kramatorsk, almost certainly did not know of the apartments that once stood here, the people and families who once lived here, and the lives that were stolen here.

But 60-year-old Valentina knows.

She might have lived on the fourth floor, but all that she owns fell here in the lobby.

She salvages what she can from the Russian strike on February 1 that Ukraine and the U.S. called indiscriminate.

She walked up to her apartment, despite the frequent air raid siren.

She has lived here longer than Ukraine has been independent.

She was in her apartment when the missile struck.

She is lucky to be alive.

Today, she uses it for storage.

This is what remains of her possessions.

The wall that used to have a window into the bathroom is now a window onto the ground below.

That's her bathtub, and the aqua tiles installed by her and her son.

VALENTINA, Resident of Kramatorsk, Ukraine (through translator): I was asleep.

And I was lucky that I was on the other side of the apartment.

Had I been sleeping on the side, you see for yourself.

NICK SCHIFRIN: So, that's your son.

She shows me videos of her son.

In 2014, he went to fight following Russia's initial invasion.

He never came back.

VALENTINA (through translator): On March 23, he would have been 44.

My life has been lived.

For 60 years, I was saving, creating this home, and now it's all gone.

There was a grocery store here.

And they got me some groceries, just strangers, total strangers.

This was the first year they have opened the store.

They called me and asked: "Do you need anything?"

I said: "I have never asked anyone for anything my whole life.

I'm very ashamed.

But I don't have anything."

And they got me groceries.

They said: "This is for you from our family."

That's it.

Everybody left.

I'm here all alone.

NICK SCHIFRIN: Artem Shalata is a Donetsk region war crimes prosecutor who is investigating the strike he calls a violation of the rules of war.

ARTEM SHALATA, Donetsk Region War Crimes Prosecutor (through translator): During this attack, a married couple died.

A 61-year-old woman and her 31-year-old daughter died.

And 17 people were wounded.

NICK SCHIFRIN: He and his fellow prosecutors visit the aftermath of many strikes, and try to find the Russian missile that can be sometimes be linked with specific units.

And they document graves of the Ukrainians whom Russians have killed with overwhelming regularity.

What is the scale of Russian crimes in Donetsk?

ARTEM SHALATA: We are overseeing investigations of more than 20,000 criminal cases, in connection with violations of the rules of war.

NICK SCHIFRIN: One of the most notorious occurred here, the Kramatorsk train station, where the horror of what happened hangs heavy for even soldiers and the memorial marks the most innocent victims.

Last April 8, hundreds of Ukrainians from the east arrived on the platform and inside the station to try and flee the war.

Suddenly, they flinched.

Human Rights Watch investigated the attack and created this animation.

At that moment, a mile-and-a-half above the station, a Tochka-U cluster bomb 20 feet long with 50 bomblets inside exploded and released its deadly submunitions, each with explosions and metal rings.

When they land, they burst into thousands of fragments and create terror.

At least 58 people died, more than 100 injured, one of the war's deadliest moments.

Left behind, the suitcases that would never be used again, the prized possession that would never be held again.

Apparently, the Russians considered the attack tit for tat.

The missile that landed here was spray-painted "Payback for our children."

IDA SAWYER, Human Rights Watch: I mean, absolutely horrific what they did.

This was a known evacuation point.

We counted over 500 people at this train station at the moment of the attack.

NICK SCHIFRIN: Ida Sawyer directs the Crisis and Conflict Division at Human Rights Watch.

IDA SAWYER: This attack at the train station clearly a violation of the laws of war and an apparent war crime.

These are people desperately fleeing war.

We have seen extensive war crimes, crimes against humanity being committed over the past year.

And it is -- it's just one thing after another.

NICK SCHIFRIN: In so many ways, Russia has taken a page from its own playbook and targeted Ukraine's most vulnerable.

This used to be a psychiatric institution, hit by four Russian rockets, one of at least eight hospitals in this city alone struck by Russia, part of what independent researchers call a nationwide campaign against Ukrainian medical facilities.

Physicians for Human Rights mapped every attack on a medical facility between February 24 and December 31.

They counted 707.

If you think this is new, you haven't been paying attention.

Russia has used the same tactics in Syria for eight years.

But now Russia is now committing a new crime.

These children might look happy for Russian propaganda cameras, but each is Ukrainian, stolen from their homeland and forcibly made Russian.

This is the reality.

Russians besieged Mariupol, and forced its children into Russia, including those of Yevhen Mezhevyi.

YEVHEN MEZHEVYI, Father (through translator): I put the children on the bus, hugged and kissed them.

CHILD (through translator): One man said he would be returned in seven years.

People said five or seven years.

CHILD (through translator): They asked me again, do you want to join a foster family or an orphanage?

NICK SCHIFRIN: They told their story in a "Vanity Fair" documentary for The Reckoning Project.

Nataliya Gumenyuk is the group's founding member.

NATALIYA GUMENYUK, The Reckoning Project: From some of the testimonies and also analytical reports and what we hear from the people, there is an attempt to indoctrinate those kids with the different policies, with the different ideas, and actually creating kind of a hatred and denial of the Ukrainian state.

NICK SCHIFRIN: Mezhevyi managed to travel to Moscow and escape with his children to Latvia.

The U.S. says Moscow's actions are taken at all levels of the Russian government, including the top.

Last week, Russian President Vladimir Putin met the presidential commissioner for children's rights in Russia, who said she -- quote -- "adopted" her own Ukrainian child.

NATALIYA GUMENYUK: I think Russia, in particularly, in previous wars in Syria, in Chechnya, they were acting with such an impunity, thinking that nobody would care.

In Ukraine, they made a mistake.

We do care.

We record.

We document.

There is the will of the people of the country to do something.

And that gives a hope that that -- the justice can be sir can prevail.

NICK SCHIFRIN: Ukraine wants to create an independent tribunal to pursue Russia's leadership.

But the U.S. has so far refused to support that, and instead prioritizes the International Criminal Court.

Accountability there will take years, while the Russian missiles keep falling.

The strike blew open a dozen homes and rained debris on the playground.

The same playground where 61-year-old Sergey Seydaliev's children used to play.

He stares at his now-destroyed home, where he lived with his parents and his family for the last 42 years.

There is so much torment here, but it's mixed with a tenacious will.

SERGEY SEYDALIEV, Resident of Pokrovsk, Ukraine (through translator): We lost all of our savings.

This is my whole life.

And now everything is gone.

Everything is gone.

I'm an older man.

But we will make it through.

Life does not stop here.

We will win, for sure, I have no doubt whatsoever.

NICK SCHIFRIN: After all the Russian crimes, most Ukrainians say the only justice would be victory.

For the "PBS NewsHour," I'm Nick Schifrin in Kramatorsk, Ukraine.