Good morning. Welcome to Axios today. It's Thursday, February 24th. I'm Nailibutu. Here's what we're following today.

Why more women of color in the U.S. are dying because of pregnancy or childbirth.

But first are one big thing. Russia launches a full-scale attack on Ukraine.

Those are air raid sirens in Ukraine's capital Keev this morning, that audio's courtesy of the AP. Ukrainian President Vladimir Zelensky told his people to stay strong as Russian forces invaded his sovereign nation by land, air and sea overnight.

Vladimir Putin ordered what he called a special military operation to quote, demilitarize, and de-nautify Ukraine.

Explosions could be heard throughout the country as Russian missile strikes were reported in multiple cities.

And Putin added a stark warning to nations who interfere. The U.S. for its part issued its own stark statement.

With President Biden saying he'll be meeting this morning with NATO allies in quote, the world will hold Russia accountable.

I asked Axios co-founder Mike Allen what he's thinking about this morning.

Nailib, everything we're seeing and hearing from Vladimir Putin is faster, broader, more aggressive than people in Ukraine had expected or certainly hoped.

It's pretty much what the Biden administration has been forecasting. We were just never sure how much bluffing we were hearing from either side.

Well, turns out Putin's buildup was no faint and that dire warnings from the White House were spot on.

Now I want to call our listeners attention to one line in Putin's invasion speech.

Waste in there was a nuclear warning. Putin said nations quote, well, face consequences greater than any U of face in history.

Unquote if they interfere with the invasion. Why this matters? This is a rare overt threat of nuclear attack.

One was chilling public warnings of the modern nuclear era.

On Capitol Hill, there's concern about how the U.S. could get further drawn into this war.

Axios' Jonathan Swan and Zach Basu spoke to chair of the Senate Intelligence Committee Mark Warner, who warned about how cyber attacks could also pull the U.S.

into an armed conflict. Zach's with us here to explain. Hey, Zach. Hey there.

So Zach, a lot of this comes down to one article in the NATO charter. What do we need to know about article five?

Article five is really the bedrock of NATO. It states that an attack on one member should be viewed as an attack on all members.

It's only been invoked once in NATO's history after 9-11. And in recent years, NATO has added cyber to the definition of possible attacks that could trigger Article five.

...