Yeah, I've never done an international/domestic connection at O'Hare either, but I've done it at the airports in Los Angeles and Charlotte and both times they made us clear customs first, claim our bags, re-check them at another kiosk and then exit to the main concourse to go back through security.
At LAX, they pulled the folks who had a quicker connection time out of line and sent them to a shorter, faster line. At Charlotte, they made no such attempt, but had agents standing by to re-book people who missed their connections.
"You drank a charm to kill John Proctor's wife! You drank a charm to kill Goody Proctor!" - Betty Parris to Abigail Williams in Arthur Miller's The Crucible