The headline doesn't even really capture the worst of the remarks:

Trump said he told Defense Secretary Pete Hegseth that the U.S. "should use some of these dangerous cities as training grounds for our military," a reference to the Democratic-run cities that he has long said have high crime rates that make them uninhabitable.

https://www.youtube.com/watch?v=gKxWz8dyKfU - 44:28 into this video.