"It's a real danger," Duckworth told David Axelrod on "The Axe Files" podcast, produced by the University of Chicago Institute of Politics and CNN, when asked about Trump's decision to name several retired military generals to key posts.
"We're the greatest nation on the face of the Earth, and the greatest democracy, because we're not a military junta," Duckworth said. "So we shouldn't be starting on that slippery slope towards it."
Duckworth, a congresswoman from Illinois who retired from the Army Reserves in 2014 with the rank of lieutenant colonel, said that concern led her to oppose a recent measure intended to clear the way for Trump's nomination of retired Marine Gen. James Mattis to serve as secretary of defense.
The measure, tacked on to a critical spending bill by Congress and signed into law by President Barack Obama earlier this month, eased a longstanding requirement that ex-military personnel be out of uniform for seven years before leading the Defense Department. Mattis retired in 2013.
In addition to Mattis, Trump has nominated retired Marine Gen. John Kelly as secretary of homeland security and retired Army Lt. Gen. Michael T. Flynn as his national security adviser.
Duckworth, who lost both legs when her helicopter was shot down in Iraq, said she remembered Mattis as a fearsome Marine commander.
"If you want to go in and you want to find and destroy the enemy and kill them, he's your guy," she said. Later, she said she came to know Mattis as the "scholarly" military strategist she has heard testify before Congress.
Yet Duckworth said she's troubled by the lack of debate or concern within Congress as to the wisdom of having someone so close to the military put in charge of running it. She said she would withhold judgment on the nomination of Mattis pending his testimony and that debate.
"Congress needs to do its job and have full oversight and have the hearings" into the matter, Duckworth said. It is only with public hearings, she argued, that "the American people know what the dangers are and what's at stake."
Generally, Duckworth said, she will make competence, not ideology, her litmus test for nominees.
"If they're qualified to do the job, they're qualified to do the job...even if I disagree with their philosophy," Duckworth stated. "If I think they can do the job, then that's the advise and consent role of the Senate."
To hear the whole conversation with Duckworth, which also includes her experience growing up in Southeast Asia as the child of a Marine; a harrowing account of the day the helicopter she was co-piloting came under attack in Iraq; why she believes it was a mistake for the Bush administration to go to war in Iraq; what she hopes to accomplish in the Senate; and much more, click on http://podcast.cnn.com
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