The nation's capital has ramped up security ahead of Biden's first State of the Union address tonight.

Up to 700 National Guard troops have been made available to assist local law enforcement, and a controversial inner-perimeter fence once again surrounds the U.S. Capitol.

The U.S. Capitol Police have also been working in tandem with local, state and federal law enforcement agencies on a "security plan to prevent any disruption to the important work of Congress," Capitol Police Chief Tom Manger said in a statement earlier this week.

-ABC News' Noah Minnie

For more live coverage of the State of the Union, head to FiveThirtyEight, which is providing updates on Biden's address as well as the Texas primary election.

"Given the current state of affairs, both foreign and domestic, tonight is a big night for the president," writes FiveThirtyEight politics reporter Alex Samuels.

Biden is expected to announce tonight that the U.S. will ban Russian carriers from its airspace, a person familiar with his remarks told ABC News.

Canada and the European Union have also issued similar bans following Russia's invasion of Ukraine.

-ABC News' Ben Gittleson

Iowa Gov. Kim Reynolds is expected to hit Biden on inflation, foreign policy and school reopenings in the GOP response to tonight's State of the Union, according to an excerpt of her speech released by Senate Minority Leader Mitch McConnell.

"Instead of moving America forward, it feels like President Biden and his party have sent us back in time to the late '70s and early '80s. When runaway inflation was hammering families, a violent crime wave was crashing on our cities, and the Soviet army was trying to redraw the world map," she said in the prepared remarks.

Keeping schools open "is only the start of the pro-parent, pro-family revolution that Republicans are leading in Iowa and states across this country," she said.

"Republicans believe that parents matter. It was true before the pandemic and has never been more important to say out loud: Parents Matter," she continued. "They have a right to know, and to have a say in, what their kids are being taught."

-ABC News' Lalee Ibssa

Biden will call on Congress to pass a "unity agenda," comprising several initiatives that have been historically popular on both sides of the aisle, an administration official said on a call with reporters Tuesday morning.

While the call went on to highlight one example of the unity agenda -- mental health care -- the term is notable. The "unity agenda" could be the reframing of his stalled Build Back Better proposal -- Biden picking and choosing portions of that package his administration believes could pass with bipartisan support.

Biden will call for mental health initiatives, in the context of worsening mental health due to the pressures of the pandemic. One especially notable one: Due to mounting evidence that social media plays a major role in mental health challenges for young people, Biden will call on Congress to strengthen social media privacy protections, ban targeted advertising to kids and demand technology companies stop collecting personal data on children, an administration official said.
-ABC News' Sarah Kolinovsky