A recent escalation of Texas’ Operation Lone Star is facing renewed scrutiny. The Justice Department plans to sue the state over a floating barrier in the Rio Grande. It’s also investigating accusations from a state trooper that agents were told to push a group of migrants - including children - back into the water. What is happening at the southern border? And how did it get so dire?   Guest: Ben Wermund, Washington correspondent for the Houston Chronicle and San Antonio Express-News If you enjoy this show, please consider signing up for Slate Plus. Slate Plus members get benefits like zero ads on any Slate podcast, bonus episodes of shows like Slow Burn and Amicus—and you’ll be supporting the work we do here on What Next. Sign up now at slate.com/whatnextplus to help support our work. Podcast production by Elena Schwartz, Paige Osburn, Anna Phillips, Madeline Ducharme and Rob Gunther. Learn more about your ad choices. Visit megaphone.fm/adchoices