Duckworth, in a speech on Saturday, called Trump a "five deferment draft-dodger" and "Cadet Bone Spurs" — a reference to the medical diagnosis the president received in 1968 that allowed him to be exempted from military service.
The Vietnam War was raging in that year, and the draft was ongoing. Trump went to military high school but never served in the military.
"I will not be lectured about what our military needs by a five deferment draft-dodger. And I have a message for Cadet Bone Spurs: If you cared about our military, you'd stop baiting Kim Jong Un into a war that could put 85,000 American troops and millions of innocent civilians in danger," Duckworth said.
The Senator for Illinois is a retired Army lieutenant colonel and Black Hawk pilot. She lost both legs after her helicopter was shot down by insurgents near Taji, Iraq, in 2004.
The U.S. military does not cease operating during the government shutdown, because it's considered an essential government service. Still, Trump said on Twitter that Democrats were "holding our Military hostage" by not supporting a funding bill.
The U.S. government shutdown will go into a third day on Monday. Non-essential services such as tourist sites and national parks are closed. But those dealing with public safety and national security continue working.
This isn't the first time Duckworth has called Trump "Cadet Bone Spurs" — she used the name in a Twitter post earlier in January.