CHICAGO (CBS) — On the fourth and final night of the virtual Democratic National Convention on Thursday night, U.S. Sen. Tammy Duckworth (D-Illinois) said Democratic presidential nominee Joe Biden would stand up for military families because he knows the danger and sacrifice involved in serving the country.

She also called President Donald Trump a “coward in chief.”

Duckworth lost both legs in 2004 while serving as a U.S. Army helicopter pilot during the Iraq War. Her helicopter was hit by a rocket-propelled grenade.

She said after she was injured, her husband, Bryan Bowlsbey, rushed to Walter Reed Army Medical Center – and served as her “rock” as she was in “unspeakable pain and unending surgeries” and as she relearned to walk.

Duckworth said Biden understands military sacrifices because he has made them himself.

“When his son, Beau, was deployed to Iraq, his burden was also shouldered by his family,” Duckworth said. She said Biden had to “muster the same strength every hour of every day.”

“That is the kind of leader our service members deserve – one who understands the risk they face and would actually protect them,” Duckworth said.

By contrast, Duckworth called President Trump a “coward in chief” who “won’t stand up to Vladimir Putin, read his daily briefings or even publicly admonish adversaries for putting bounties on our troops heads.

“As president, Joe Biden would never let tyrants manipulate him like a puppet. never pervert our military to promote his own ego. he would never turn his backs on our troops,” Duckworth said. “Joe Biden would stand up for what’s right, stand tall for our troops, and stand strong against our enemies.”

She added, “Donald Trump doesn’t serve to call himself commander in chief for another four minutes, let alone another four years.”

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Duckworth first ran for Congress in Illinois’ 6th Congressional District in 2006 as Republican incumbent Henry Hyde retired, but lost to Republican Peter Roskam. But Duckworth ran for Congress again in the 8th Congressional District in 2012 and won, defeating Republican incumbent Rep. Joe Walsh.

Duckworth was elected to the U.S. Senate in 2016, defeating Republican incumbent Mark Kirk.