Brennan thinks he has it in the bag. He's convinced Mueller is on their side. His tweet yesterday was something of a veiled threat. They're just bullies and think they can bully their way out of this one like they always do.
https:// www.washingtonexaminer.com/news/former-cia-director-john-brennan-trump-should-stay-tuned-on-robert-muellers-russia-investigation