Rep. Lauren Boebert heckles Biden as he talks about his late son during the State of the Union

Rep. Lauren Boebert (R-Colo.) interrupted President Biden as he discussed his late son, Beau Biden, and troop exposure to burn pits on March 1. (Video: The Washington Post)

Democrats and Republicans in Washington at times displayed unity as President Biden addressed the nation at his first State of the Union on Tuesday night. Members of both parties stood to applaud the Ukrainian ambassador and Biden’s announcement that U.S. airspace would close to Russian planes.

But sharp divides between the parties were evident, too, including when the president brought up his late son, Beau Biden, an Iraq War veteran who died of brain cancer in 2015. President Biden on Tuesday called on Congress to pass legislation to aid veterans exposed to toxins while serving in Iraq and Afghanistan — a problem he said leads to cancers “that would put them in a flag-draped coffin.”

He was then interrupted by Rep. Lauren Boebert (R-Colo.), who yelled, “You put them there. Thirteen of them!”

Boebert appeared to be referencing the 13 troops killed in a suicide attack last year during the final days of the chaotic U.S. withdrawal from Afghanistan.

“One of those soldiers was my son, Major Beau Biden,” the president continued.

Biden has, for years, expressed that his son’s death might have been caused by exposure to toxins while he served in Iraq and Kosovo. Beau Biden was an officer in the Army National Guard.

Democrats immediately booed Boebert, and one of them shouted, “Kick her out!” Neither Boebert nor the White House responded to messages from The Washington Post following the incident.

The outburst was not the only tense moment of the night. Some in the chamber — including Boebert and Rep. Marjorie Taylor Greene (R-Ga.) — seemed to mock the president as he went on with his speech. Both laughed at some lines, uttered retorts and live-tweeted the event.

“Here’s another way to fight inflation,” Boebert wrote on Twitter. “Resign.”

She later tweeted, “You fired our troops. Don’t ever act like you support them.”

The Colorado Republican, who wore a black shawl with the words “Drill Baby Drill” on the back, wrote at least 50 tweets lambasting Biden throughout his speech. The attire referenced her support of increased drilling for petroleum and gas — a stance she has tweeted about in the past and a 2008 Republican campaign slogan.

Greene also critiqued Biden’s speech in several tweets.

“Joe Biden wants us to tackle ‘mental health.’ I agree. We must start with the presidency,” Greene wrote.

By the end of the address, Boebert tweeted, “When Biden said flag draped coffins I couldn’t stay silent. I told him directly he did it. He put 13 in there. Our heroic servicemen and women deserve so much better.”

When Biden said flag draped coffins I couldn't stay silent. I told him directly he did it. He put 13 in there.

Our heroic servicemen and women deserve so much better.

— Lauren Boebert (@laurenboebert) March 2, 2022

Matt Viser and Marianna Sotomayor contributed to this report.