Last night’s edition of “The Rachel Maddow Show,” on MSNBC, collapsed under the weight of the news it was charged to deliver. At the very end of the hour, a story broke from the Associated Press about the “ ‘tender age’ shelters” housing panicked young children who have been separated from their families at the border. “Trump administration officials have been sending babies and other young children,” it read. But Maddow couldn’t read it. She pressed through the first sentence with her eyes locked on the page.